I thought this was a joke and a shot at current OS manufacturers like "The next apple update will have a brand new never before seen thing called a "drop down menu!" Lol
You could use a larger screen and list the menu out. You can get the code to do this from build of Marlin firmware for 3d printers. That code also includes an encoder wheel with push button.
@@logicone5667 Not really ;) I redefine the existing navigation keys. There was a poll last year what RCT users want and the result was to keep the existing GUI. But there have so many ICs been added in the last year that it is time to improve it a little bit I guess.
12:47 if it doesn't have a dedicated back button by design, the easiest way will be implement in the firmware a "hold" (long press) state on the select button to jump back .
I was gonna say you could potentially read out the firmware data using AVR Studio or something (may need to whack some 'bodge' wires onto the micro to access the pins it uses for ISP if there's no ISP header) and just write that function in probably fairly easily, but if he's adding it anyway then there's no need :D
I was thinking of putting the whole thing in a case and wiring an extra button to activate both, should also be able to connect a turning knob like that with some in between stuff.
Psh.. I could totally design and build one of these myself. .... just as soon as I get done with the other 8000 projects I said that about. 😒 Hm. Maybe I should just buy one, so I could actually use it before I expire.
You're right, it needs a rotary switch with a button and submenus. Also it's be cool to have a few memory buttons that could be custom shortcut to chips you test frequently.
Yes, they need to look at what some of the 3D printer firmwares do with a menu and rotary switch and select button. Very effective way to handle long lists.
@@redace001 the 3d printer lcd boards are made (in general) to an open "standard" and the cheapest often come with sd reader and rotary encoder on the board. to the point i integrate them into projects im using lcds on because its easier
Remember to set the contrast for the new LCD. Also, I would mount it in a wooden case with a lid, and print the extended chip list as either a table on the inside is the lid, or as a little booklet that sits next to the device.
Love the "warts and all" aspect of this video. Thank you for showing your mistakes along the way, as we can learn much more from them than just seeing the working unit.
Great video, really useful device to have in your arsenal. Love the way you keep any mistakes in your videos, rather than editing them out. Makes for a far better viewing experience. Thanks Noel 👍
Love this video for two reasons. The first being its very well produced with clear explanations. It also shows the human side of many of us and the common mistakes and problem solving we all do from time to time such as working through the problem of programming the fuses and firmware, picking the wrong display, forgetting the contrast setting, etc. It's "reality" UA-cam. I really want to pull the trigger on this and build one. Keep up the fine work on your very informative videos sir.
Don't underestimate the amount of work required to design and develop the software for something like this. The idea the they make this available at cost is truly generous. I think they can look at your comments regarding the user interface. It might not be a trivial exercise but doable to re-purpose some of the switches in different modes of the menu. Very good and thorough review. As usual saw a video pop up from your channel and jumped to view it. Great work.
Oh, absolutely! The amount of work he's put into this and he continues to put into it is amazing! A part of the quirks of it is due to how it's grown since it started. At the beginning, when it only tested a handful of chips, something like a rotary button wasn't nearly as important as it is now. Glad you liked it and thanks for the kind words!
These LCD screen have the same controller and ALL work with a virtual display of 2 lines x 40 columns. The physical LCD will always just display a part of this virtual screen. If you write sequential chars on the display, they will be written to the RAMbut will not be displayed. A 4x20 display will have the first half of line 1 in line 1, the second half on line 2, then 1st half of line 2 on line 3 and the last half of line 2 on line 4 (or something like that, it's 30 years ago that I wrote a Siemens ES102 display emulation on such a Toshiba LCD display).
@@bigbeef2654 Starting w/something simple through the ISP interface should be inexpensive and 9600bps would cover what I saw on the LCD. Being able to load the chip database updates from the uSD/TF card or USB, rather than AVR reload would rock.
Many years ago (1985 to be precise), I was part of a design team for a RAM tester for use in factories. It was about a metre across and was too heavy for one person to move. Things have changed.
@@NoelsRetroLab When I was a student, I measured prices in how many 2114L chips that was - I had an Acorn Atom at the time and I wanted to expand it all the way to 12K.
I have just created a brushless motor controller, and it has a Hitachi display like that one. It has several pages of PID controls and other presets. The user interface uses a rotary encoder just exactly as Noel described. It's a fast effective way to implement any UI. The rotary encoder has a pushbutton built in, so you only need to hold one rotary control and you can do everything.
I talked to Stephan about it and he's aware of that option, but apparently it's not possible because it uses more pins and the microcontroller is maxed out already. But we are getting an option for a back button, so that already will be pretty good.
@@NoelsRetroLab Hi Noel. Something sounds a little odd there though, because the encoder (with built in push to select/deselect switch) only needs three I/O pins, and it could do everything. You already had four switches and you're talking about a new one. I like the rotary encoder best, and I think your original observation is spot on! :-)
@@1pcfred fuck the pc. The win updates, firewalls, antivirus and all the rest. Standalone diag tools are always better/portable and also can be used instantly..
just a tip...you could have used the arduino board to connect to the ICSP and program the chip! (that how i programmed my z80-mbc2 a few weeks ago)..you didnt have to buy that "programmer" EDIT: i see you mentioned that at the end of the vid! cool board...thanks for the look Noel
Thanks Noel. Love that you left the mistakes is… Great manuals often have the TLDR problem. We are all humans :-) I have a RAM tester (no idea what kind of model it is - it was pricy), which also measures the maximum speed of the RAM chip. I've found a bunch, where the maximum speed was slower than what was promised on the label…
Glad you liked it! I think measuring the exact speed could be really interesting, I suspect you need a dedicated DRAM tester for that with a pretty powerful CPU to get that kind of accuracy. Someone brought up they were working on something like that in the previous tester comments I think.
I think it was Adrian Black who ran into a similar issue with some RAM chips for one of his Tandy computers where the chips were a bit slower than what the label said. This led him to initially think the chips were bad, but once a viewer had alerted him to the issue, it turned out the chips were okay.
Very impressive variety and amount of chips it can test. I would think having the ability to interface with a computer and use a simple VT52 interface would help vice relying on a LCD screen - but it does make this tester as a convenient standalone tester. An alternative tester that I recently acquired is the Tauntek IC tester that I saw reviewed by CuriousMarc YT channel. I like this tester because during testing it is able to measure current drawn by the chip and measure pin voltages are within VOL and VOH levels and even tristate levels. It’s helpful to see borderline chips that other testers may just declare pass even though the chip may pull way more current than normal. The tester reviewed here and the Tauntek tester, together, can be some great testers to both have to complement a viable work bench. Thanks for the review on this tester and highlight mistakes during the build that could easily happen to any of us.
I have been all over the internet. Where does one get a parts list and determine what parts are needed to build this thing. Can a parts kit be found, or do you need to part it out one part at a time?
Why stop there, a nextion display with an HMI would be even better.... it could even display graphs of the chip outputs in realtime etc... honestly a ice40hk + some voltage level conversion would probably make a better tester this probably can't test that the ram is acutally performing at its specs as its too slow.
For better component selection ease, how about a master table with a four digit (or more if need) code for each device to be tested? Keeping the PCB markings the same for the benefit of other functions:
Press "Reset" button to start the device selection process. Press the "Select" button multiple times to increase the most significant digit of the device code displayed on LCD - press "OK" button - display moves right to the next digit - press "Select" button multiple times to enter the next digit - press "OK" - and so forth. Press and HOLD the "Select" button to rapidly decrement current digit with the digit position moving left to the previous digit position after a "0" count. "Reset" button to start over.
This is a brilliant device and I have nothing but praise for the amount of work the creators put into designing this super useful tool. Definitely on my list of things to get hold of! I'm thinking in terms of the user interface, having a number pad might be a good idea as the list of supported chips grows, so you could reference to a list number and jump straight to the chip you want.
Agreed. It's truly amazing. The number pad could be quite useful, but I suspect that wouldn't work with the current microcontroller and would add quite a bit of complexity.
You jumpstarted the car without your feed on the ground, literally. Considering that you wired the clock signal but not ground (if I didn't miss another connection in the scene) I wonder what kind of loops were in your setup to work at all. A real feat!
Interesting. I didn't think much about it at the time. I must have lucked out with the grounds being common, probably because both devices were powered from the USB ports of the same computer.
I appreciate this video so much. I ordered my BOM and TOTALLY missed the screen too :) Thanks for all the great content as always. I'm a big (lurking) fan.
That is an amazing piece of kit that any retro restorer should have in their tool chest. From what I've seen on the creator's site though, the code does not seem to be open source. This is not a deal breaker, but I think it would allow for the community to contribute patches, like the one Noel refers to about a possible back button feature. To be absolutely clear though, I am planning on purchasing one of these for my own retro restoration projects, and having the ability to determine if memory chips and supporting logic chips are good or not is invaluable in my opinion.
I think I'm sold on this. In the future making it so it can identify unidentified chips would be a fantastic feature if it can be added! Also adding a full keypad to directly enter chip numbers would make things easier too. If/when I get one I think I'm going to try to design a 3D printable case for it.
You won't regret it 😃 A friend of mine used a small plastic case he had for something else that's JUST the right size of the tester. So he can carry it around really easily. I believe he also changed the power supply to use batteries, so he made it 100% portable. Really neat.
Wow! As always, your videos are really fun and well done! Thanks, Noel, for showing to us so many devices and computers. This UA-cam channel is pure gold!
8:00 It may just be 4MHz, but I kind of expected some problems with signal integrity, seeing as you've only used one wire to connect the clock signal, meaning the ground return path was all the way through the pcb, ICSP connector, ribbon, programmer, USB port, the other USB port and finally the arduino's USB cable. Although if you really didn't change much between the two tries it's more likely it was just a dodgy connection. Either way, it was an interesting way to get the chip working without a high voltage programmer, so kudos to you!
Nice gadget and work, as always. If you are planning to use it constantly, as you already told us, I would suggest you(you know me...) to ask the manufacturer for 3 things to implement in the next update: First: For those who use the small screen, there should be an option to have a vertical or horizontal scrolling, in order to be able to see all of the available info. This might be good even for the big screens. Second: If we want to go back and choose the previous chip type, as you had the need to do, this could have been done by holding down the "next" button or using a combination of buttons, in order to go back one selection. Third: The ability to control the whole system(or even set some parameters like the fore-mentioned scrolling) from the computer, like all of the other programmers in the market do, as far as I know. I think that these thingies would be nice to have. Happy testing!
The 44256 were extremely common memory chip in the early 90s. Neary every 1MB VGA card was equipped with 8 of them. The GUS classic used these chips as sample RAM. Some 286/386SX mainboards that offered DIP socket memory as well as SIMMs accepted banks made of 4 44256 (for 16 bit data) and 2 41256 (for parity) to build a bank of 512K. So indeed, the chips are exotic for you, but that's just because they are newer than the retro stuff you usually deal with.
Been there and done that with “bricking” an AVR. With an AVR you can feed its clock directly to an output pin. So I use that from a second AVR to provide a clock.
Great video, you actually mentioned this tester a while ago and that is how I found it. I bought the pcb and parts immediately and have build one myself a few months ago. I had to laugh when I saw the wrong zif socket early in the video, as I made the exact same mistake ;-) I flash mine with an arduino (programmed as isp) and this works fine, however you do have to disconnected the sd reader to program, so there's a tip for you and others. I would also like to mention that support from Stephan is just awesome, I have mailed him a few couple of times when I had a 'problem' and he is very helpful and all issues were solved within a day! Next to retro computers I repair arcade pcb's and this thing is a must have for this...
Awesome board and step by step video. I saw the limitations on 13:00 . The only suggestion would be get rid of the button controllers and the display using the computer as a main interface via usb. That would simplify the overall board, and make it simpler.
Yes, you probably could. In retrospect I should have tried that since I'm very comfortable with the Arduino, but I went down that way since it was the recommended way in the manual (even if that wasn't exactly the recommended programmer).
@@NoelsRetroLab This just needs the encoder wheel and graphic screen, even mono like most ender printers would improve using it by a massive amount. Perhaps the 2560 is already at it's limits for IO and memory.
Yes you can, but you'd still need to use AVRdude in command mode since I believe the code is supplied as a HEX file. There are very cheap ICSP AVR programmers available from the chinese markets that work well too.
I would use the same 4 buttons but with this actions: Up, Down, OK, Back. Reset would be just Up + Down pressed together. That would allow any navigation using a menu style interface. As always, great video Noel!
Nice. I would love to see this evolve into a unit that can connect with an Amiga or ST, then check all common computer DIP chips, such as 68000, VIC, Pokey and so on, and have full Workbench / GEM support for easier navigation and feedback.
I've replaced that type of buttons quite a few times in my projects as they fail. Rotary digital step control would be much better. I remember buying an IC tester from Maplin back in the 90s which had a board with an ISA connector...I used it mainly for 74 series. This new board covers a lot of different types of chip. Testing is slow but probably ok for occasional use. Checking the monitor screen carefully is essential to avoid missing any errors. Previous experience programming with Arduinos would help . The Manual looks good and is probably essential and read through carefully before starting the build. Nice one, Noel.
Yes, it's the type of project you can relax while building it: easy components, lots of similar ones next to each other... It took a good 2-3 hours to build, but it wasn't stressing like some SMD projects can be.
@@NoelsRetroLab I built the OSSC some time back... that definitely wasn't any pleasant experience. Also taking in account that I built it only using the soldering iron and without using hot air station
I would build it just so I can say, "I built this". :-) Maybe someone can come up with an easy mod that would enable a "backspace" function in the library? I assume it would not be easy. It would probably involve code change in the processor as well as added hardware. (?)
08:20 more impressive that electrical current flows in a loop, but yet only one single strand of wire connects the (temporary) pulse generator to the chip tester
My grandfather on my mother's side was very headstrong and almost never read the manual on anything. Perhaps it was his education (he had a masters' degree in electronics engineering).
🤣 I totally get it. I'm much more of the mentality of start messing with something, and when I run into some issues, then I read the manual. Just my personality I guess.
I just bought one based on this video and can't wait to put it together. Regarding the price, I spent a few weeks on a project because an SRAM chip was counterfeit. If I had this device, it would have paid for itself in time alone.
I think your rotary encoder switch idea is a real good idea. I would retrofit that on my board if the firmware would handle it. I really like this project. and it has been very handy. And thanks for you video.
I know this is 2 years ago but the best solution would be a usb port and software running on an external pc to type in the chip name you’re looking for and control of all the functions
This device looks amazing! Not just for retro computing, but just general repair. Are there any plans to make this more commercially available globally?
It is an amazing device! 😃 Stephan might pitch in, but this is not his primary business, so I doubt he'll make it more commercially available. However, if there's a lot of demand, I wonder if it would be worth of him to team up with some small company to produce kits.
My first thought on seeing this is that it could be useful for testing newly acquired chips to see if they're counterfeit before installing them. I wouldn't mind seeing how well it works for that.
@@NoelsRetroLab turned out well but now you've got me holding out for the rotary encoder redesign. I could be waiting even longer for that. Doubt I can hold out! ;)
Interesting, that works out to about USD$130, which is not a lot less than I paid for my Innoventions RAMCheck. Granted that only came with the default module adapter, so you'd need a lot of different adapters to test other kinds of memory, including chip memory, so that would add up (if you can even find them). The main advantage of the RAMCheck is that it also tests performance, not just functionality, so if the chips on your SIMM are marked 60ns, it will tell you whether it meets that performance or not. I've actually found SIMMs marked 60ns performing at 50ns speeds with no errors. The other advantage is it's a lot quicker. It can perform a whole lot more tests in less than a couple of minutes, and that's on a multi-MB SIMM, not a single chip with 256Kbits. Anyway, the Retro Chip Tester is probably better value than an Innoventions tester, since they're not easy to come by. I should probably look into getting one, if nothing more than to test all the chip memory I've got on faulty boards. At least that would rule out a RAM issue with those boards.
Interesting, I wasn't aware of that RAMCheck. The fact that it measures performance means it has to be a lot more powerful, so that's certainly a unique feature the Retro Chip Tester couldn't really do. But I agree that it's a fantastic device for the money, which may seem a lot at first sight, but it really isn't given all it does.
@@NoelsRetroLab Oh yeah, and testers like the RAMCheck cost thousands new, so the fact that the Retro Chip Tester isn't as quick definitely isn't a bad compromise.
Awesome video and great inspiration. OK, OK, I admit I've been putting off putting this together for a year!!! I am going to go start right now... Until I inevitably get to the point where I ordered the wrong part or programmer.
This looks pretty great, but as someone who has no issue with hand soldering surface mount, I would prefer a more compact SMD version. Agreed about the rotary input 100%
I can see how an SMD version would be more convenient for people with experience (or to assemble automatically) but this is clearly more approachable by more people. Other than the sourcing part, assembling it was really easy, so it's not even a bad second or third soldering project 😃
That's the theory. But then you need to line it perfectly, and check for shorts, and check that every pin is perfectly touching the pad... 😃 I actually haven't done anything quite that small yet, but I'm sure I will soon.
When you try, and get super frustrated with all the bridging and janky bonds, don't forget: MORE FLUX. :-D Lots of liquid flux and and copper braid to clean up. Then you'll be all set, and TH parts will be the ones you start to dread. :-)
@@NoelsRetroLab The best way is a solder mask, solder paste and a hot plate. Scratch that the best way is to have the board come with the part soldered to it. They definitely did it the former way at the board house though.
Excelente placa en formato modular y con un manual que explica desde como armarla hasta como usarla, me recuerda mucho al homebrew computer club y la filosofia de armar las cosas uno mismo sabiendo como funcionan y dejandolas abiertas para modificarlas y expandirlas, gran video!
I really wish you bloggers would give these sources a heads-up so they can either ramp up their inventories or make arrangements for a one-time bulk production run. So many great retro testing tools out there, and every time a story is run, the developer is slammed for orders within hours - leaving the rest of us to wait until production quantities are even available. It's not like these designs are pushed out to OSH Park for self-service ordering.
I have been in touch with Stephan for a while leading up to this, but remember this is a hobby project, not his full-time job. So it's only natural that it will lead to a shortage for a while.
Rotary encoders are expensive! The button setup would be fine but I agree, there should be a back button. Some combination could be added with a firmware update I'm sure. Might be nice to even let you put the menu / chip data on the SD card so you can select only the chips you want to test from a list on your computer to make it more convenient. Submenus kinda already exist with the jump function. A simple (short) test option would be nice though. A feature that would be nice would be load testing the outputs / current draw during idle and usage. That could turn this from hobbyist diagnostic tool to industrial engineering sample analyzer real fast. Real wishful thinking here but writing E/E/PROM chips would definitely be in the cards for this and I don't think it would be that hard to verify contents for them either. This could be an extremely powerful tool if it's given just a few extras!
So out of curiosity, what was that HM486*** chip's entire part number? I ask because the Hitachi HM4864-2, HM4864-3, HM4864P-2 and HM4864P-3 chips are slightly different from the Texas Instruments TMS4164-15NL you started with. They have 128 row address strobe cycles, as opposed to the 256 of the TMS parts, so I wonder if that affected the test outcome?
Great tool, great review. Thank you. I was aware of this kit, even exchanged a few msgs with its designer last year. I only fix and maintain my modest collection of ZX Spectrums, so a bit on the expensive side for me, but yet, as you have already said, it is a very valuable tool for those who make money doing retro repairs, well worth the price for them, I wouldn't think twice if I were one. You are right on the idea of a rotary switch, I am sure the designer will consider that on the next hardware revision. Also since now you are used to buying parts twice :-) you should get a yellow positive image 4x20 LCD for that. Totally pin compatible, much better contrast and viewing angle, just a little more on the price tag but worth it. I've stopped using these "blue" LCDs on my projects long time ago, they are just a waste of money.
Thanks! I think a rotary input is out of the question because the microcontroller is maxed out as far as pins. So it would have to be a significantly different revision. But that would be fantastic. You're right about the screen. You're probably talking about the OLED ones, right? I looked into it, but they're insanely expensive at the moment (around 40€).
@@NoelsRetroLab No, not the OLED ones, same screen, same technology but positive image and yellow/green backlight. A graphic OLED screen will require too much change in code, there are OLED equivalents to that dot matrix screen but they are too expensive. Adding a rotary encoder will not require any extra pins, there are IO pins already assigned to those push buttons, they can be used for the rotary encoder and even sparing a couple of pins. All it needs is a daughter board to solder on the relevant section of the PCB to connect to those pins and some code change for a rotary driven menu system. This is the LCD I am talking about: www.aliexpress.com/item/32679234720.html Here is a better link, even the sales photo shows just how much better is the positive image ones: www.aliexpress.com/item/1005001694530172.html
Well, that was fun! All you need now is a custom-designed 3D-printed case for it, and Bob's your uncle. The user interface you described (using a rotary pulser) seems like it would be do-able as a daughter card, no?
Yes, it can easily be done with a daughter card that will solder on the existing push button pads. Very easy and non-costly way to do it, even the existing kit owners can buy that and upgrade. All it needs a software revision and that's not hard at all.
@@NoelsRetroLab I love a good mechanical keyboard. Maybe use a single mechanical clicky switch for a nice back button, or is that going a bit too far :D
Nice. The common TL866 programmer also tests many logic IC’s and memory chips, but this device looks like it also covers more of the earlier memory chips. Looks like a fun project to add to my project list queue. ;)
@@NoelsRetroLab Yes, latest version tests 285 logic devices, and only 10 SRAM’s starting from the 6116 (no earlier devices). No DRAM tests supported. Of course the TL866 is primarily a Programmer, supporting over 16,000 devices. The few devices it tests is just a bonus. Strangely, the CMOS and TTL logic list also includes devices 6821 (Motorola PIA ?!?), and 8155, 8255, 8259, 8279 ? Not sure I want to stick one of my PIA’s in there to see if it tests it. LOL
Cool test gear. I would enjoy building it, but would have very little use for it. I repair, (or sometimes adapt and break), Spectrums, so I'm already sorted for test equipment for them. :)
The PCBs you can order them directly from the designer (first link in description). The ZIF socket I found it from aliexpress.com/item/32831052786.html Good luck!
@@NoelsRetroLab - Ordered the sockets, thanks! BUT, went to designers site and could not find where to order the board's! It just kept running me around in circles!!
I guess the not-so-intuitive interface is the typical problem with projects that start small and then get big: I guess this project started with a few compatible chips, and this kind of interface was ok then; but the list grows and grows, and the interface works, so you don't even think about it being obtuse until someone outside the project tells you so.
I wonder if the USB programmer you used was capable of powering the board. I noticed the power adapter was not plugged in while you were programming the AVR. You may have been unknowingly powering the device through the clock pin (rectifying the 5V clock signal with the esd protection diode(s)). I've seen microprocessors powered in this manner; Not good, but it can power the device to allow it to program.
Sometimes I wish there was more willingness to surface mount soldering in projects like this. Something like that chip would not be massively difficult to solder, it is just another skill to learn, and a useful skill at that. Why should we leave all surface-mount work to those big assembly plants? :) I get that it wouldn't be for everyone so can't fault the creators of this project, but still to me it feels like a shame. Its a self assembly kit, let us self assemble :) Excellent overview Noel, as always!
You're right that's a skill, but it's one that is harder to acquire and comes with practice and time. I'd be willing to do that now, but probably not 2-3 years ago. If he's trying to reach as many people as possible, through-hole is still the way to go (although this project is specialized enough that maybe assuming SMD soldering skills would be reasonable).
Because surface mount is not hobbyist friendly. The industry did not come up with surface mount to make our lives better. I can assure you of that. The stuff absolutely sucks for prototyping. It sucks to try to salvage it too. Basically SMT sucks all around for electronics experimenters. But you do you.
I recorded around 8 hours of footage in total for this video, which I had to cut down to about 20 minutes. So of course there are cuts and things change. Sometimes I even change the order of events slightly if it helps with the flow of the narrative better.
That's very cool. I hope to make my own in a few years when I'm better at embedded development. One thing I'd like to add to this board is the feature to dump all bad addresses to a computer file (or PuTTY). Is it possible for these bad bits to serve as sort of encryption? I remember bad in the floppy days some developers put bad sectors for copy protection.
Great video. Couldn't you just power the board to get the clock signal from the crystal? I was actually surprised the jumpstarting worked because there was no ground connected between the arduino and the board.
The problem is that the crystal doesn't provide a "full" clock signal (square, 0-5V) but just more of a triangle signal with very little amplitude. And since the fuses of the microcontroller were expecting the full clock signal, that wasn't enough. You're right about the ground part. I think I lucked out because all the power is coming from USB ports on the computer and it happened to work that way. Oops!
@@NoelsRetroLab This confused me in the video, too, until I read this comment and realized that the board uses just a crystal directly connected to the MCU, and not an external crystal oscillator. (Or this is my understanding at the moment.) A crystal does not provide a clock signal at all; it's a passive device that will help guide an externally generated signal to a given frequency if driven correctly. Thus if just a crystal is used to help clock the MCU, the MCU must be configured to know that there's a crystal across those pins so it can enable its internal clock generator circuitry and drive the crystal. If the MCU is configured for an external clock, rather than internal clock generator with external crystal, there will be no clock since there's nothing on the board to provide it. There's often confusion between a crystal, of which the one in the video is a typical example, and a _crystal oscillator._ The latter generally is a much larger square or rectangular four pin device, requires +5 V, and includes both a crystal and additional clock generation circuitry so that you'll get a clock output on one of the pins when you power it up.
I think the whole unit would improve with a PC interface and have the UI on a PC screen. You basically need a PC to make the thing. So why not a PC to use it?
Very useful and awesome device. For me the 64K question is how many of the chips on an Apple ][c motherboard could this device test ? Could this device be extended / designed to test retro computer CPUs ?
Good question. I suspect it could check most of them. But get the full list and check. CPUs are out for now because they're 40 pins. I suppose it may be possible to make an adaptor, but it would have to be specific to each CPU, so probably not ideal for that.
For all who need a back button: The next firmware release will have one. - Update: v19 has been released (new menu, new switch assignments)
That's great news! Thanks Stephan! I'm really looking forward to the next firmware release. (I just pinned your comment so everybody can see it).
I thought this was a joke and a shot at current OS manufacturers like "The next apple update will have a brand new never before seen thing called a "drop down menu!" Lol
You could use a larger screen and list the menu out. You can get the code to do this from build of Marlin firmware for 3d printers. That code also includes an encoder wheel with push button.
@@logicone5667 Not really ;) I redefine the existing navigation keys. There was a poll last year what RCT users want and the result was to keep the existing GUI. But there have so many ICs been added in the last year that it is time to improve it a little bit I guess.
You really should have an option to sell this as a kit.
12:47 if it doesn't have a dedicated back button by design, the easiest way will be implement in the firmware a "hold" (long press) state on the select button to jump back .
Or use the back/jump buttons as "back/forward" and make a long press on either of them speed up the scrolling through the devices over time.
Stephan just told me that he removed an unnecessary combination and added the back functionality for the next firmware. Yay! 😃
@@NoelsRetroLab Awesome! Now I REALLY want one!! :-)
I was gonna say you could potentially read out the firmware data using AVR Studio or something (may need to whack some 'bodge' wires onto the micro to access the pins it uses for ISP if there's no ISP header) and just write that function in probably fairly easily, but if he's adding it anyway then there's no need :D
I was thinking of putting the whole thing in a case and wiring an extra button to activate both, should also be able to connect a turning knob like that with some in between stuff.
Psh.. I could totally design and build one of these myself. .... just as soon as I get done with the other 8000 projects I said that about. 😒
Hm. Maybe I should just buy one, so I could actually use it before I expire.
Haha, and you could use it as part of your 8000 projects too 😃
Ha ha ha never a truer statement said!!
You're right, it needs a rotary switch with a button and submenus. Also it's be cool to have a few memory buttons that could be custom shortcut to chips you test frequently.
I agree. It does have something about frequently used chips which I didn't look in detail, but you may already be able to do exactly that.
Yes, they need to look at what some of the 3D printer firmwares do with a menu and rotary switch and select button. Very effective way to handle long lists.
@@redace001 the 3d printer lcd boards are made (in general) to an open "standard" and the cheapest often come with sd reader and rotary encoder on the board. to the point i integrate them into projects im using lcds on because its easier
Remember to set the contrast for the new LCD. Also, I would mount it in a wooden case with a lid, and print the extended chip list as either a table on the inside is the lid, or as a little booklet that sits next to the device.
Great idea about the case and putting the list there!
Love the "warts and all" aspect of this video. Thank you for showing your mistakes along the way, as we can learn much more from them than just seeing the working unit.
Thank you! I try to keep mistakes, especially when there's something to be learned from them.
Great walk through from start to finish, even point out the room to improve, I think the author will appreciate your work.
Great video, really useful device to have in your arsenal. Love the way you keep any mistakes in your videos, rather than editing them out. Makes for a far better viewing experience. Thanks Noel 👍
Glad you enjoyed it, bonehead mistakes and all! 😃
Love this video for two reasons. The first being its very well produced with clear explanations. It also shows the human side of many of us and the common mistakes and problem solving we all do from time to time such as working through the problem of programming the fuses and firmware, picking the wrong display, forgetting the contrast setting, etc. It's "reality" UA-cam. I really want to pull the trigger on this and build one. Keep up the fine work on your very informative videos sir.
Thank you for the great feedback! I'm really glad to hear you liked it, mistakes and all 😃
Perfect timing for me, as I've recently launched into a retrocomputing project. Thanks so much for this build and review!
Don't underestimate the amount of work required to design and develop the software for something like this. The idea the they make this available at cost is truly generous. I think they can look at your comments regarding the user interface. It might not be a trivial exercise but doable to re-purpose some of the switches in different modes of the menu. Very good and thorough review. As usual saw a video pop up from your channel and jumped to view it. Great work.
Oh, absolutely! The amount of work he's put into this and he continues to put into it is amazing! A part of the quirks of it is due to how it's grown since it started. At the beginning, when it only tested a handful of chips, something like a rotary button wasn't nearly as important as it is now.
Glad you liked it and thanks for the kind words!
Just the reference and look-up tool is a huge gift to the retro community. Sincere thanks to 8-bit Museum for that.
is not at cost :)) not even close.
These LCD screen have the same controller and ALL work with a virtual display of 2 lines x 40 columns. The physical LCD will always just display a part of this virtual screen. If you write sequential chars on the display, they will be written to the RAMbut will not be displayed. A 4x20 display will have the first half of line 1 in line 1, the second half on line 2, then 1st half of line 2 on line 3 and the last half of line 2 on line 4 (or something like that, it's 30 years ago that I wrote a Siemens ES102 display emulation on such a Toshiba LCD display).
I was about to write the same comment haha
They're fun and easy to work with, very fun as a first project to make your own library
Isn't a 20*4 display actually a set of two 2*20 displays?
From memory - bad memory could be wrong -, there is 2 types of 4x20. I think it's just a couple of pins on the end that are different.
This machine is great, but it seriously needs a USB port and an associated PC application. That interface is far too clunky as it stands.
no doubt? just a simple serial text based application running at 9600 baud
Or a keypad to directly enter chip numbers
@@bigbeef2654 Starting w/something simple through the ISP interface should be inexpensive and 9600bps would cover what I saw on the LCD.
Being able to load the chip database updates from the uSD/TF card or USB, rather than AVR reload would rock.
Many years ago (1985 to be precise), I was part of a design team for a RAM tester for use in factories. It was about a metre across and was too heavy for one person to move. Things have changed.
Haha, seriously! As well as the prices of the DRAM itself! 😃
@@NoelsRetroLab When I was a student, I measured prices in how many 2114L chips that was - I had an Acorn Atom at the time and I wanted to expand it all the way to 12K.
Yeah, as soon as I saw the interface I immediately thought "that should really be a rotary encoder with velocity" ;)
I have just created a brushless motor controller, and it has a Hitachi display like that one. It has several pages of PID controls and other presets. The user interface uses a rotary encoder just exactly as Noel described. It's a fast effective way to implement any UI. The rotary encoder has a pushbutton built in, so you only need to hold one rotary control and you can do everything.
I talked to Stephan about it and he's aware of that option, but apparently it's not possible because it uses more pins and the microcontroller is maxed out already. But we are getting an option for a back button, so that already will be pretty good.
@@NoelsRetroLab Hi Noel. Something sounds a little odd there though, because the encoder (with built in push to select/deselect switch) only needs three I/O pins, and it could do everything. You already had four switches and you're talking about a new one. I like the rotary encoder best, and I think your original observation is spot on! :-)
oh man, this thing needs a rotary encoder soo baaad.
It needs a PC interface. Then you could dispense with that LCD screen and the buttons. Everyone is going to have a PC.
@@1pcfred fuck the pc. The win updates, firewalls, antivirus and all the rest. Standalone diag tools are always better/portable and also can be used instantly..
just a tip...you could have used the arduino board to connect to the ICSP and program the chip! (that how i programmed my z80-mbc2 a few weeks ago)..you didnt have to buy that "programmer" EDIT: i see you mentioned that at the end of the vid!
cool board...thanks for the look Noel
Totally worth it. I've got a couple of machines that I would love to use this on!
It really is!
Thanks Noel. Love that you left the mistakes is… Great manuals often have the TLDR problem. We are all humans :-)
I have a RAM tester (no idea what kind of model it is - it was pricy), which also measures the maximum speed of the RAM chip. I've found a bunch, where the maximum speed was slower than what was promised on the label…
Glad you liked it! I think measuring the exact speed could be really interesting, I suspect you need a dedicated DRAM tester for that with a pretty powerful CPU to get that kind of accuracy. Someone brought up they were working on something like that in the previous tester comments I think.
I think it was Adrian Black who ran into a similar issue with some RAM chips for one of his Tandy computers where the chips were a bit slower than what the label said. This led him to initially think the chips were bad, but once a viewer had alerted him to the issue, it turned out the chips were okay.
Very impressive variety and amount of chips it can test. I would think having the ability to interface with a computer and use a simple VT52 interface would help vice relying on a LCD screen - but it does make this tester as a convenient standalone tester.
An alternative tester that I recently acquired is the Tauntek IC tester that I saw reviewed by CuriousMarc YT channel. I like this tester because during testing it is able to measure current drawn by the chip and measure pin voltages are within VOL and VOH levels and even tristate levels. It’s helpful to see borderline chips that other testers may just declare pass even though the chip may pull way more current than normal.
The tester reviewed here and the Tauntek tester, together, can be some great testers to both have to complement a viable work bench.
Thanks for the review on this tester and highlight mistakes during the build that could easily happen to any of us.
I have been all over the internet. Where does one get a parts list and determine what parts are needed to build this thing. Can a parts kit be found, or do you need to part it out one part at a time?
Easiest is to contact the developer. ;)
I put one together. the build was really satisfying, it came up the first time. I used it to test some ZIP dram.
The 4-line LCD would look better if you adjust the contrast. You shouldn't see boxes behind each character.
You're right. I think they were more noticeable on camera for some reason, but I need to lower it a bit.
Why stop there, a nextion display with an HMI would be even better.... it could even display graphs of the chip outputs in realtime etc... honestly a ice40hk + some voltage level conversion would probably make a better tester this probably can't test that the ram is acutally performing at its specs as its too slow.
He adjusted it for his eyes. The camera is at a different angle, so it saw different contrast.
Those blue and white backlit LCDs have superb contrast when adjusted right.
For better component selection ease, how about a master table with a four digit (or more if need) code for each device to be tested? Keeping the PCB markings the same for the benefit of other functions:
Press "Reset" button to start the device selection process. Press the "Select" button multiple times to increase the most significant digit of the device code displayed on LCD - press "OK" button - display moves right to the next digit - press "Select" button multiple times to enter the next digit - press "OK" - and so forth. Press and HOLD the "Select" button to rapidly decrement current digit with the digit position moving left to the previous digit position after a "0" count. "Reset" button to start over.
This is a brilliant device and I have nothing but praise for the amount of work the creators put into designing this super useful tool. Definitely on my list of things to get hold of! I'm thinking in terms of the user interface, having a number pad might be a good idea as the list of supported chips grows, so you could reference to a list number and jump straight to the chip you want.
Agreed. It's truly amazing. The number pad could be quite useful, but I suspect that wouldn't work with the current microcontroller and would add quite a bit of complexity.
You jumpstarted the car without your feed on the ground, literally. Considering that you wired the clock signal but not ground (if I didn't miss another connection in the scene) I wonder what kind of loops were in your setup to work at all. A real feat!
Interesting. I didn't think much about it at the time. I must have lucked out with the grounds being common, probably because both devices were powered from the USB ports of the same computer.
Very cool - glad there are things like this out there to test these old chips.
I appreciate this video so much. I ordered my BOM and TOTALLY missed the screen too :) Thanks for all the great content as always. I'm a big (lurking) fan.
I have this tester in version 1.2h and I dont regret buying it. It is very useful and today I can use it without problem (as like I´m sleeping).
That is an amazing piece of kit that any retro restorer should have in their tool chest. From what I've seen on the creator's site though, the code does not seem to be open source. This is not a deal breaker, but I think it would allow for the community to contribute patches, like the one Noel refers to about a possible back button feature.
To be absolutely clear though, I am planning on purchasing one of these for my own retro restoration projects, and having the ability to determine if memory chips and supporting logic chips are good or not is invaluable in my opinion.
I just wanted to watch a minute into the video and now I watched the full. Super interesting review, thx!
I think I'm sold on this.
In the future making it so it can identify unidentified chips would be a fantastic feature if it can be added! Also adding a full keypad to directly enter chip numbers would make things easier too. If/when I get one I think I'm going to try to design a 3D printable case for it.
You won't regret it 😃 A friend of mine used a small plastic case he had for something else that's JUST the right size of the tester. So he can carry it around really easily. I believe he also changed the power supply to use batteries, so he made it 100% portable. Really neat.
Incredible. A few days ago I was wondering if a product like this existed and this pops up in my recommended.
Great video.
Thank you! I guess UA-cam is reading minds now. That's pretty scary! 😃
Great video Noel!
Love to see the mistakes. Best way to learn 😁
Thanks! Glad that was useful. We all make those kind of mistakes sometimes 😃
You need a case for the tester. It is very easy to drop something (a chip maybe?) and do a short circuit on the board.
I was thinking the same especially the amount of times they were taken over the top of the PCB
Excellent video! Absolutely loved it!
Glad you enjoyed it!
Wow! As always, your videos are really fun and well done! Thanks, Noel, for showing to us so many devices and computers. This UA-cam channel is pure gold!
My pleasure!
8:00 It may just be 4MHz, but I kind of expected some problems with signal integrity, seeing as you've only used one wire to connect the clock signal, meaning the ground return path was all the way through the pcb, ICSP connector, ribbon, programmer, USB port, the other USB port and finally the arduino's USB cable. Although if you really didn't change much between the two tries it's more likely it was just a dodgy connection. Either way, it was an interesting way to get the chip working without a high voltage programmer, so kudos to you!
Nice gadget and work, as always. If you are planning to use it constantly, as you already told us, I would suggest you(you know me...) to ask the manufacturer for 3 things to implement in the next update:
First: For those who use the small screen, there should be an option to have a vertical or horizontal scrolling, in order to be able to see all of the available info. This might be good even for the big screens.
Second: If we want to go back and choose the previous chip type, as you had the need to do, this could have been done by holding down the "next" button or using a combination of buttons, in order to go back one selection.
Third: The ability to control the whole system(or even set some parameters like the fore-mentioned scrolling) from the computer, like all of the other programmers in the market do, as far as I know.
I think that these thingies would be nice to have. Happy testing!
The 44256 were extremely common memory chip in the early 90s. Neary every 1MB VGA card was equipped with 8 of them. The GUS classic used these chips as sample RAM. Some 286/386SX mainboards that offered DIP socket memory as well as SIMMs accepted banks made of 4 44256 (for 16 bit data) and 2 41256 (for parity) to build a bank of 512K.
So indeed, the chips are exotic for you, but that's just because they are newer than the retro stuff you usually deal with.
Bah, fancy newfangled hardware! 🤣 Edit: They probably came from an Amstrad PPC or a PCW.
Been there and done that with “bricking” an AVR. With an AVR you can feed its clock directly to an output pin. So I use that from a second AVR to provide a clock.
Great video, you actually mentioned this tester a while ago and that is how I found it. I bought the pcb and parts immediately and have build one myself a few months ago. I had to laugh when I saw the wrong zif socket early in the video, as I made the exact same mistake ;-)
I flash mine with an arduino (programmed as isp) and this works fine, however you do have to disconnected the sd reader to program, so there's a tip for you and others.
I would also like to mention that support from Stephan is just awesome, I have mailed him a few couple of times when I had a 'problem' and he is very helpful and all issues were solved within a day!
Next to retro computers I repair arcade pcb's and this thing is a must have for this...
Haha, I'm glad I'm not the only one making those silly mistakes 😃 And yes, Stephan has been amazing with his patience and support! Top notch!
Awesome board and step by step video.
I saw the limitations on 13:00 . The only suggestion would be get rid of the button controllers and the display using the computer as a main interface via usb.
That would simplify the overall board, and make it simpler.
A great bit of kit, Can't you program the atmega from an Arduino in ISP mode instead of buying another programmer ?
Yes, you probably could. In retrospect I should have tried that since I'm very comfortable with the Arduino, but I went down that way since it was the recommended way in the manual (even if that wasn't exactly the recommended programmer).
@@NoelsRetroLab This just needs the encoder wheel and graphic screen, even mono like most ender printers would improve using it by a massive amount. Perhaps the 2560 is already at it's limits for IO and memory.
Yes you can, but you'd still need to use AVRdude in command mode since I believe the code is supplied as a HEX file. There are very cheap ICSP AVR programmers available from the chinese markets that work well too.
I agree on using a rotary encoder. In fact most of the ones I use have a button press function built-in to them just for that reason.
I would use the same 4 buttons but with this actions: Up, Down, OK, Back. Reset would be just Up + Down pressed together. That would allow any navigation using a menu style interface. As always, great video Noel!
Nice. I would love to see this evolve into a unit that can connect with an Amiga or ST, then check all common computer DIP chips, such as 68000, VIC, Pokey and so on, and have full Workbench / GEM support for easier navigation and feedback.
I've replaced that type of buttons quite a few times in my projects as they fail. Rotary digital step control would be much better.
I remember buying an IC tester from Maplin back in the 90s which had a board with an ISA connector...I used it mainly for 74 series.
This new board covers a lot of different types of chip. Testing is slow but probably ok for occasional use.
Checking the monitor screen carefully is essential to avoid missing any errors. Previous experience programming with Arduinos would help .
The Manual looks good and is probably essential and read through carefully before starting the build.
Nice one, Noel.
Great vid ! I can't justify to buy the components and build this board but it's nice to know it exists. Thanks for letting us know about it
You're welcome! It's definitely a bit on the costly side, but I know it can be really worth it for certain people depending on the projects they do.
I would just have fun building and soldering this device, it's like meditation... :D
Yes, it's the type of project you can relax while building it: easy components, lots of similar ones next to each other... It took a good 2-3 hours to build, but it wasn't stressing like some SMD projects can be.
@@NoelsRetroLab Good ole THT :D
@@NoelsRetroLab I built the OSSC some time back... that definitely wasn't any pleasant experience. Also taking in account that I built it only using the soldering iron and without using hot air station
@@NoelsRetroLab Is the PCB available for order? If yes then how much is it? Is there a gerber file to order PCB myself?
I would build it just so I can say, "I built this". :-) Maybe someone can come up with an easy mod that would enable a "backspace" function in the library? I assume it would not be easy. It would probably involve code change in the processor as well as added hardware. (?)
Love the trouble shooting on the ATMega. I've had quite a few bricked ATMegas and never thought to introduce an external clock. Good stuff!
Thank you! 👍
08:20 more impressive that electrical current flows in a loop, but yet only one single strand of wire connects the (temporary) pulse generator to the chip tester
My grandfather on my mother's side was very headstrong and almost never read the manual on anything. Perhaps it was his education (he had a masters' degree in electronics engineering).
🤣 I totally get it. I'm much more of the mentality of start messing with something, and when I run into some issues, then I read the manual. Just my personality I guess.
I just bought one based on this video and can't wait to put it together. Regarding the price, I spent a few weeks on a project because an SRAM chip was counterfeit. If I had this device, it would have paid for itself in time alone.
Fantastic! Great to hear. Good luck with it. Yes, it can quickly pay for itself with all the counterfeit chips going around.
I think your rotary encoder switch idea is a real good idea. I would retrofit that on my board if the firmware would handle it. I really like this project. and it has been very handy. And thanks for you video.
I've also build the tester, great device and nice support/development/updates from Stephan S.
Super & great analysis. Nice comments to help to improve the design.
Thank you! 👍
You can use any Arduino to flash other ATmegas. The sketch is in the Arduino IDE.
I know this is 2 years ago but the best solution would be a usb port and software running on an external pc to type in the chip name you’re looking for and control of all the functions
This device looks amazing! Not just for retro computing, but just general repair. Are there any plans to make this more commercially available globally?
It is an amazing device! 😃 Stephan might pitch in, but this is not his primary business, so I doubt he'll make it more commercially available. However, if there's a lot of demand, I wonder if it would be worth of him to team up with some small company to produce kits.
My first thought on seeing this is that it could be useful for testing newly acquired chips to see if they're counterfeit before installing them. I wouldn't mind seeing how well it works for that.
Exactly! First thing to do as soon as you get any chips in the mail.
That is my plan as well. I like to test all IC's before putting into inventory.
Been wondering when this video was coming, now I know why it took extra long! 😂
Yeah, there were a few bumps along the way 😃
@@NoelsRetroLab turned out well but now you've got me holding out for the rotary encoder redesign. I could be waiting even longer for that. Doubt I can hold out! ;)
Terrific video...I learned more from your errors than I would have otherwise.
I'm glad my errors were good for something! 😃
Excellent video and explanation. Thank you!
Very cool tester! Thanks for reviewing it!! Something more to add to my Christmas list! :)
You're welcome! It's such a great piece of kit. You'll love it 😃
Interesting, that works out to about USD$130, which is not a lot less than I paid for my Innoventions RAMCheck. Granted that only came with the default module adapter, so you'd need a lot of different adapters to test other kinds of memory, including chip memory, so that would add up (if you can even find them). The main advantage of the RAMCheck is that it also tests performance, not just functionality, so if the chips on your SIMM are marked 60ns, it will tell you whether it meets that performance or not. I've actually found SIMMs marked 60ns performing at 50ns speeds with no errors. The other advantage is it's a lot quicker. It can perform a whole lot more tests in less than a couple of minutes, and that's on a multi-MB SIMM, not a single chip with 256Kbits.
Anyway, the Retro Chip Tester is probably better value than an Innoventions tester, since they're not easy to come by. I should probably look into getting one, if nothing more than to test all the chip memory I've got on faulty boards. At least that would rule out a RAM issue with those boards.
Interesting, I wasn't aware of that RAMCheck. The fact that it measures performance means it has to be a lot more powerful, so that's certainly a unique feature the Retro Chip Tester couldn't really do. But I agree that it's a fantastic device for the money, which may seem a lot at first sight, but it really isn't given all it does.
@@NoelsRetroLab Oh yeah, and testers like the RAMCheck cost thousands new, so the fact that the Retro Chip Tester isn't as quick definitely isn't a bad compromise.
Awesome video and great inspiration. OK, OK, I admit I've been putting off putting this together for a year!!! I am going to go start right now... Until I inevitably get to the point where I ordered the wrong part or programmer.
I was on the fence until the ROM trick , very cool device.
It is! And I feel I didn't even show half of what it can do. There's a lot more than that hidden in the menus.
This looks pretty great, but as someone who has no issue with hand soldering surface mount, I would prefer a more compact SMD version.
Agreed about the rotary input 100%
I can see how an SMD version would be more convenient for people with experience (or to assemble automatically) but this is clearly more approachable by more people. Other than the sourcing part, assembling it was really easy, so it's not even a bad second or third soldering project 😃
Put a mini wave tip on your iron and that surface mount IC is one of the easiest things to put on there - literally done in under a minute
That's the theory. But then you need to line it perfectly, and check for shorts, and check that every pin is perfectly touching the pad... 😃 I actually haven't done anything quite that small yet, but I'm sure I will soon.
When you try, and get super frustrated with all the bridging and janky bonds, don't forget: MORE FLUX. :-D Lots of liquid flux and and copper braid to clean up. Then you'll be all set, and TH parts will be the ones you start to dread. :-)
@@NoelsRetroLab The best way is a solder mask, solder paste and a hot plate. Scratch that the best way is to have the board come with the part soldered to it. They definitely did it the former way at the board house though.
Excelente placa en formato modular y con un manual que explica desde como armarla hasta como usarla, me recuerda mucho al homebrew computer club y la filosofia de armar las cosas uno mismo sabiendo como funcionan y dejandolas abiertas para modificarlas y expandirlas, gran video!
That 256k x 4 DRAM is super popular in (S)VGA cards from 1988 to 1993, I have probably a hundred or so of these ICs (all inside some old (S)VGA cards)
Amazing work of art. Hats off to 8Bit-Museum!
There must be a list of all the IC's it can test. Where is link for that?
So this kit is so retro that it ships with a real manual, amazing!
For those who don't get it, old manuals were entire service manuals. :)
It is not that retro. It is a pdf, not printed on paper ;)
@@8BitMuseum true! Can't have everything. 😉
I really wish you bloggers would give these sources a heads-up so they can either ramp up their inventories or make arrangements for a one-time bulk production run.
So many great retro testing tools out there, and every time a story is run, the developer is slammed for orders within hours - leaving the rest of us to wait until production quantities are even available. It's not like these designs are pushed out to OSH Park for self-service ordering.
I have been in touch with Stephan for a while leading up to this, but remember this is a hobby project, not his full-time job. So it's only natural that it will lead to a shortage for a while.
@@NoelsRetroLab Murphys Law: It doesn't matter how many devices you have in stock. It's never enough.
Rotary encoders are expensive! The button setup would be fine but I agree, there should be a back button. Some combination could be added with a firmware update I'm sure. Might be nice to even let you put the menu / chip data on the SD card so you can select only the chips you want to test from a list on your computer to make it more convenient.
Submenus kinda already exist with the jump function.
A simple (short) test option would be nice though.
A feature that would be nice would be load testing the outputs / current draw during idle and usage. That could turn this from hobbyist diagnostic tool to industrial engineering sample analyzer real fast.
Real wishful thinking here but writing E/E/PROM chips would definitely be in the cards for this and I don't think it would be that hard to verify contents for them either. This could be an extremely powerful tool if it's given just a few extras!
So out of curiosity, what was that HM486*** chip's entire part number? I ask because the Hitachi HM4864-2, HM4864-3, HM4864P-2 and HM4864P-3 chips are slightly different from the Texas Instruments TMS4164-15NL you started with. They have 128 row address strobe cycles, as opposed to the 256 of the TMS parts, so I wonder if that affected the test outcome?
Great tool, great review. Thank you. I was aware of this kit, even exchanged a few msgs with its designer last year. I only fix and maintain my modest collection of ZX Spectrums, so a bit on the expensive side for me, but yet, as you have already said, it is a very valuable tool for those who make money doing retro repairs, well worth the price for them, I wouldn't think twice if I were one. You are right on the idea of a rotary switch, I am sure the designer will consider that on the next hardware revision. Also since now you are used to buying parts twice :-) you should get a yellow positive image 4x20 LCD for that. Totally pin compatible, much better contrast and viewing angle, just a little more on the price tag but worth it. I've stopped using these "blue" LCDs on my projects long time ago, they are just a waste of money.
Thanks! I think a rotary input is out of the question because the microcontroller is maxed out as far as pins. So it would have to be a significantly different revision. But that would be fantastic.
You're right about the screen. You're probably talking about the OLED ones, right? I looked into it, but they're insanely expensive at the moment (around 40€).
@@NoelsRetroLab No, not the OLED ones, same screen, same technology but positive image and yellow/green backlight. A graphic OLED screen will require too much change in code, there are OLED equivalents to that dot matrix screen but they are too expensive. Adding a rotary encoder will not require any extra pins, there are IO pins already assigned to those push buttons, they can be used for the rotary encoder and even sparing a couple of pins. All it needs is a daughter board to solder on the relevant section of the PCB to connect to those pins and some code change for a rotary driven menu system.
This is the LCD I am talking about: www.aliexpress.com/item/32679234720.html
Here is a better link, even the sales photo shows just how much better is the positive image ones: www.aliexpress.com/item/1005001694530172.html
@@NoelsRetroLab With a little luck you can get one under 20 EUR. This is 22 EUR www.aliexpress.com/item/32929491915.html
I wish I had that chip tester years ago. In order to test ICs I'd always have to build some circuit on a breadboard.
Well, that was fun! All you need now is a custom-designed 3D-printed case for it, and Bob's your uncle. The user interface you described (using a rotary pulser) seems like it would be do-able as a daughter card, no?
Yes, it can easily be done with a daughter card that will solder on the existing push button pads. Very easy and non-costly way to do it, even the existing kit owners can buy that and upgrade. All it needs a software revision and that's not hard at all.
Have you used the CUSTOM option, a video on programming a custom chip would be good and very helpful
13:30 A rotary encoder with a clickable button when you push it and an added back button, just because I like a good rotary encoder with a click :D
I'm all for clicks (says as he types this on a mechanical keyboard 😃).
@@NoelsRetroLab I love a good mechanical keyboard. Maybe use a single mechanical clicky switch for a nice back button, or is that going a bit too far :D
Nice. The common TL866 programmer also tests many logic IC’s and memory chips, but this device looks like it also covers more of the earlier memory chips. Looks like a fun project to add to my project list queue. ;)
Exactly. And I think the TL programmer doesn't test DRAMs at all, right? I need to get the latest update to be sure.
@@NoelsRetroLab and it only also tests SRAMs 32k x 8 up. But it can burn EPROMs and thousands of other devices, so other target group.
@@NoelsRetroLab Yes, latest version tests 285 logic devices, and only 10 SRAM’s starting from the 6116 (no earlier devices). No DRAM tests supported. Of course the TL866 is primarily a Programmer, supporting over 16,000 devices. The few devices it tests is just a bonus.
Strangely, the CMOS and TTL logic list also includes devices 6821 (Motorola PIA ?!?), and 8155, 8255, 8259, 8279 ?
Not sure I want to stick one of my PIA’s in there to see if it tests it. LOL
Cool test gear. I would enjoy building it, but would have very little use for it. I repair, (or sometimes adapt and break), Spectrums, so I'm already sorted for test equipment for them. :)
Exactly. If you're mostly doing one platform, it's probably total overkill.
Where do I go to buy the 2 boards, and the CORRECT ZIF Socket? I hope the designer adds being able to backup on a chip selection!
The PCBs you can order them directly from the designer (first link in description). The ZIF socket I found it from aliexpress.com/item/32831052786.html Good luck!
@@NoelsRetroLab - Ordered the sockets, thanks! BUT, went to designers site and could not find where to order the board's!
It just kept running me around in circles!!
I guess the not-so-intuitive interface is the typical problem with projects that start small and then get big: I guess this project started with a few compatible chips, and this kind of interface was ok then; but the list grows and grows, and the interface works, so you don't even think about it being obtuse until someone outside the project tells you so.
Excellent video :D This would be so great to test ram and different chips. I will ask if texelec can build and sell these preassembled.
I bought a 1.2k version board about a year and a half after you did this video and it has a back button, someone was listening to you...
Awesome video. Thanks for sharing the whole journey, mistakes included :)
Glad you enjoyed it!
I wonder if the USB programmer you used was capable of powering the board. I noticed the power adapter was not plugged in while you were programming the AVR. You may have been unknowingly powering the device through the clock pin (rectifying the 5V clock signal with the esd protection diode(s)). I've seen microprocessors powered in this manner; Not good, but it can power the device to allow it to program.
Sometimes I wish there was more willingness to surface mount soldering in projects like this. Something like that chip would not be massively difficult to solder, it is just another skill to learn, and a useful skill at that. Why should we leave all surface-mount work to those big assembly plants? :)
I get that it wouldn't be for everyone so can't fault the creators of this project, but still to me it feels like a shame. Its a self assembly kit, let us self assemble :)
Excellent overview Noel, as always!
You're right that's a skill, but it's one that is harder to acquire and comes with practice and time. I'd be willing to do that now, but probably not 2-3 years ago. If he's trying to reach as many people as possible, through-hole is still the way to go (although this project is specialized enough that maybe assuming SMD soldering skills would be reasonable).
Because surface mount is not hobbyist friendly. The industry did not come up with surface mount to make our lives better. I can assure you of that. The stuff absolutely sucks for prototyping. It sucks to try to salvage it too. Basically SMT sucks all around for electronics experimenters. But you do you.
Wow, that looks like a really useful device!
Absolutely! It's earned a permanent spot on my workbench.
@@NoelsRetroLab Is it able to distinguish LS/TTL from HC/CMOS chips?
@@DmitriyBychkov No, it can't, sorry.
17:31 Look at the LCD. The text changes when he moves on to the next chip.
I recorded around 8 hours of footage in total for this video, which I had to cut down to about 20 minutes. So of course there are cuts and things change. Sometimes I even change the order of events slightly if it helps with the flow of the narrative better.
That's very cool. I hope to make my own in a few years when I'm better at embedded development. One thing I'd like to add to this board is the feature to dump all bad addresses to a computer file (or PuTTY). Is it possible for these bad bits to serve as sort of encryption? I remember bad in the floppy days some developers put bad sectors for copy protection.
Great video! Could you tell us where you finally find out the ZIF support?
Thanks! I finally got the correct one from this vendor: aliexpress.com/item/32831052786.html
@@NoelsRetroLab Thank you !
Great video.
Couldn't you just power the board to get the clock signal from the crystal? I was actually surprised the jumpstarting worked because there was no ground connected between the arduino and the board.
The problem is that the crystal doesn't provide a "full" clock signal (square, 0-5V) but just more of a triangle signal with very little amplitude. And since the fuses of the microcontroller were expecting the full clock signal, that wasn't enough.
You're right about the ground part. I think I lucked out because all the power is coming from USB ports on the computer and it happened to work that way. Oops!
@@NoelsRetroLab This confused me in the video, too, until I read this comment and realized that the board uses just a crystal directly connected to the MCU, and not an external crystal oscillator. (Or this is my understanding at the moment.)
A crystal does not provide a clock signal at all; it's a passive device that will help guide an externally generated signal to a given frequency if driven correctly. Thus if just a crystal is used to help clock the MCU, the MCU must be configured to know that there's a crystal across those pins so it can enable its internal clock generator circuitry and drive the crystal. If the MCU is configured for an external clock, rather than internal clock generator with external crystal, there will be no clock since there's nothing on the board to provide it.
There's often confusion between a crystal, of which the one in the video is a typical example, and a _crystal oscillator._ The latter generally is a much larger square or rectangular four pin device, requires +5 V, and includes both a crystal and additional clock generation circuitry so that you'll get a clock output on one of the pins when you power it up.
Dang it Stefan!! Another cool project I can't make.
Looks like the chip selection could use a rotary encoder with some logic for scrolling fast.
Annnd you. just said that
I think the whole unit would improve with a PC interface and have the UI on a PC screen. You basically need a PC to make the thing. So why not a PC to use it?
Very useful and awesome device. For me the 64K question is how many of the chips on an Apple ][c motherboard could this device test ? Could this device be extended / designed to test retro computer CPUs ?
Good question. I suspect it could check most of them. But get the full list and check. CPUs are out for now because they're 40 pins. I suppose it may be possible to make an adaptor, but it would have to be specific to each CPU, so probably not ideal for that.