I pulled a Compaq computer from the trash. Opened the case and it was built like a tank as well. Some one had took a hammer to the hard disk pins, which I straightened. After reassembly, I booted the machine and everything was on the hard disk ! It was an insurance company with all client data. I did the right thing and reformatted the disk. I also had a Compaq portable. My father-in-law was an IBM executive and was interested in it so i sold it to him.
If I remember correctly the 401 error for the Compaq usually meant open port. If you had a parallel or a serial port loopback connector you could test if I am right or not. I was a Compaq repair tech back then. There were loopback connectors for the serial (RS232, 9 and 32 pin)port, power connector port, parallel port, BNC port (network card testing) and others for testing purposes.
Love this series on the Compaq. I wanted a Deskpro so much when they first came out. I tested my wife's patience drooling over one at the local Compaq shop. Couldn't afford one and settled for a cheaper IBM clone. At least I was able to use one at work every now and then.
Thanks for the great video! BTW, INT 21 / INT 20 sequence is a bit redundant :) As I remember, DOS (especially 2.0+) has a bunch of ways to exit a program: INT 20, RET (which jumps to INT 20), INT 21 with AH = 0, INT 21 with AH = 4C and AL = (recommended) and a couple of others like terminate-and-stay-resident function or short jump to address 0 in COM-file (which again does INT 20). So the actual exit from the program in the video is caused by INT 21 with AH set to 0 implicitly by DOS before the program entry. Back in the days when I was a kid my first PC programming experience was writing short assembly programs in DEBUG utility because I had a trouble with floppy disk when tried to copy BASIC interpreter to my XT clone :)
Some thoughts about the floppy controller: - I've counted four tantalum capacitors, replace them - there is a 10 turn trimmer pot. Turn it in both directions, to clean the contacts in it (count how much you turn it to find the original position, also measure its resistance before and after. Counting the revolutions is not accurate, since you might not notice when you hit the end stop, some trimpot click when you hit the end stop, but most clicks only in one direction. - if nothing helps, start resoldering it. If it doens't help either, fill the vias with solder, and solder the component pins on both sides. It might be a broken via. - if this doesn't help either, you have a nice ornament to hang it on the wall :) Edit: Oh, and Merry Christmas!
The video card looks exactly like the card in the Compaq portable. The CRT on the portable connects to the dual row header above the controller chip. I don't remember what J405 does, but J402 is composite video.
Hey Adrian. I'm new to your channel but I just want to say fairplay for your videos. I had one of these Compaq computers and I can't tell you how many hours of the D&D game Hillsfar I have under my belt. Great memories.
@Adrian Black, would love to watch your deep dive into C=64 or Amiga disk copy protection -- what studios did to their diskettes to protect them from being copied by the end-user's disk drive. I was reading the old Kracker Jax Revealed Trilogy PDF online. Some copy protection methods were quite fascinating. I'm still baffled over the random bit flipping on original disks vs the static bit on copied disks.
A small anecdotal detail: the Deskpro I had in the early 90s (which was a hand-me-down from my father who bought it new) had two floppies, one in each of the upper bays. The bottom bays had two blanks. From this, I would guess that a configuration with two floppies and an HDD would have had the floppies in the top bays and the HDD in one of the bottom bays. I don't know for sure which one, but the blank bay cover and the hard drive front look the same except for the light, so it doesn't matter much from an aesthetic point of view. When I acquired an HDD later, I put it in the bottom right, but I don't remember 25 years later if there was a particular reason why. Looking at the floppies that came in your box, I would guess it initially had a single floppy and an HDD. Also... 401 means Unauthorized! Clearly the machine knows you're using a controller card from a different OEM! (kidding-- that's what the 401 HTTP response code means, if you don't know.)
I love those old orange screens, now I have watched this I am going to have to buy a vintage PC with an orange screen... Bugger, more expense to satisfy my wants lol. Great video, thanks for sharing...
If I remember correctly dir -w is to list the directory across the width of the screen. It would come in handy for long directory listings.
5 років тому+11
I guess the C program has the error, that argv[1] should be used instead of argv[2] at the stricmp() calls. Seems to be a typical off-by-one error, because the first element is actually the zeroth element :) EDIT: never mind, just noticed after reloading the page that this is already discussed below :)
I wonder if it is possible to arrange for argv[2] to be pointing at the right string. Say running CPQ SPEED FAST FAST immediately followed by CPQSPEED FAST. I bet DOS safely zeros everything. (BTW: I think this comment was first.)
@@galier2 Yeah, I see that, but I suggest running the program twice. First time it does have argv[2] set FAST but doesn't execute. Second time it does execute and but argv[2] is undefined. Hopefully, the memory has been reused without wiping, leading to argv[2] remaining FAST.
It's been a long time, and my memory is sketchy, but what most PC's see as LPT1 is reversed on early Compaq's, try setting the jumpers on your multi-I/O to LPT2 for the onboard parallel port. That is why you are getting the 401, since all Deskpro's shipped with a parallel port.
I have the complete hardware maintenance and service documentation for the original deskpro if you need any information out of it. I also have the technical reference manual for the 386/25 model, but it also covers some of the expansion cards of the earlier models.
Composite colour artefacting does work in PAL, but you have to use horizontal lines, rather than vertical. You can also switch the palette using colours of a similar shade at the full 50Hz, which on a CRT(at least a PAL composite one) will result in the 2 colours blending together from beam persistence. Mayhem in Monsterland(1993) for C64 makes great use of this. A game I would rate as good as any NES game, save maybe Mario 3. Still have my original tape.
There’s something serious about those old amber displays. I grew up with full color Amiga 4096 color goodness. But there was always a side eyed respect for those amber displays like they were for launching nukes and stuff while I was toying around with my color display playing Dungeon Master.
Great video! I have heard that the cracks becomes beacuse the steal dosent shrink but the plastic get smaler with time. but the metal stay the same. and when it shrink they crack becuse the pressure
I recently had a floppy controller that would just randomly stop working. I spent ages trying to figure out the problem, but eventually gave up. I ended up doing the same thing as you, at least until I can get an 8 bit card. I disabled the game port on mine though, as it seemed to cause a conflict.
Is that board covered in rosin core flux. As the flux dries out the impedance decreases. It's all so much harder to remove. The flux can be causing shorting. You might try soaking it in isopropyl and scrubbing it. Or replacing the ceramic caps.
Maybe there are some dry solder joints on that floppy board. Sometimes these are impossible to see. I would go over with an soldering iron to reflow the solder
They're probably changing pallet data on the card between scanlines. This was a trick sometimes used on the Sega Genesis to get more than 64 colors on screen at a time, and it's very timing critical.
I think it was very unusual for PCs to have an 8086 CPU and 8bit slots, I know a lot certainly had custom expansion slots that were 16bit and directly connected to the CPU. I guess this included some kind of compatibility bridge for 8 bit slots while keeping 16bit memory access.
Interesting. I have a couple other 8086 machines but those are 8-bit slots too ...... I also have a 286 (Tandy 1000TL) that also only has 8-bit slots ... so a total waste LOL. The 8086 is still not great versus a 286 because the data and address bus is still multiplexed on the same pins on the CPU, so you aren't getting that much of a performance increase.
@@adriansdigitalbasement Perhaps it got more common later in the 80s for low end PCs since 8086 CPUs wouldn't have been any real cost saving over the 8088, and PC hardware compatibility was just as important as software by then. A while back I read through loads of old reviews of early 80s PC clones and the 8086 ones were more or less 100% compatible through DOS and the BIOS, but wouldn't work with any 8 bit PC expansions.
@@adriansdigitalbasement Nice to see they have a solution - I'm well versed in the RTC 1287 battery mod, this would have been an interesting challenge, what with the ROM being on top of the internal battery. :)
www.tindie.com/products/cyberneticsys/tandy-1000-hxsx-smartwatch/ This is the link to the modern version -- it's the DS1216 clock chip. Gotta say a very slick implementation and this works on other computers like the Apple II even. And yes I've mded several of those DS1287 to add the external battery -- a great fix. I will probably one day get around to checking this out since it really isn't working anyway.
The way the controller card was acting sounded like a possible broken solder joint, but not having a clue where to start, maybe going the easy-route and doing the modern day graphics card repair of baking the card might help re-flow the solder? If it's a lost cause as it is, there's not much to lose, just remember to protect any melty plastic parts with foil to avoid making a mess... :)
Hi there, awesome video. I have a question. I got my hands on an amber monitor but i don't have the compaq. I wonder how i might be able to rig it so it works as a CGA monitor for another computer. Is that realistic? perhaps the resolution is hyper specific to the system it was made for? I thought it would be awesome to hook it up to my Sinclair 1000 or maybe I'll get my hands on CGA PC down the road..
Hey, where can we get ahold of the NO-SLOT-CLOCK CLOCK, XTCLOCK and CLKINIT utilities? Been searching for like an hour, and can't turn up anything. I know it's been a couple years, so sorry for the late ask lol
@@adriansdigitalbasementI am watching it now. I love old computers. Grew up with a 80386 that my dad bought down here in Klamath Falls. I'm hoping to find a 486 one day. I love messing with DOS and want to learn more. I love your videos!
Speaking of getting cf cards not willing to boot, after fdisk, formating and transferring the system files use the command fdisk /mbr on the cf card. Should fix the boot issue. Works on my Pii machines.
so why wait until the summertime to retr0brite the machine? I thought the point of the UV box setup was to be rid of the need to wait for summer to come around before you wanted to de-yellow stuff. wouldn't it be easier to just get a rubbermaid and line it with foil tape and work your magic that way?
As far as I know you can use IDE on this 16-bit multi-function cards in 8-bit slot with CF card and XT-IDE BIOS configured for this (16-bit ISA IDE in 8-bit mode). Never tried this though.
19:33: Please be careful with this. It is possible to damage some CGA monitors by treating them as MDA/Hercules, and it is possible to damage some MDA/Hercules monitors by treating them as CGA. Depending on the monitor, doing that can effectively be a killer poke -- see the Wikipedia article -- but yes, I also know this from personal experience.
what's with that selfmade "memory card" ? is there a video about it or schematics and stuff ? i'd like to build a ram expansion card for my 5170, but if i can use an already existing design, i would not have to reinvent the weel one more time
One desperation move for the floppy controller is to replace the crystal oscillator. If the machine suffered any physical shock in its life, the crystal could have a fracture and quit working reliably.
I guess it's a legacy from CP/M, upon which MS_DOS was originally modelled... I found this: thestarman.pcministry.com/asm/debug/debug2.htm#W which explains a bit about it, but it's not for the novice or the faint-of-heart ;)
God damn those Panasonic floppy drives. I have two different ones, which both have some fully cracked plastic parts rendering them useless. No such problems with TEAC's.
Hope you can read this, just a quick suggestion, I guess you could try doing what I do to old corroded PCBs, which is using a very soft sandpaper to sand down the connector at the lower part, just quite a bit until you see the metal shinny, as it should be.
I have don a lot of research for your 401 issue and yes, my friend with same computer (lille different config though) and with 16bit expansion for fdd, has the very same error but the pc worx 100%
Hey, I googled this quite a few times now and wasn't able to find something. Where can I get such an IBM ANSI-file? Also, would this work with the MDA card? Your help would be very much appreciated. Thanks in advance.
I didn't see any comments on this... but how did you disable the onboard floppy BIOS? I've got a compaq portable that I'm playing with a floppy upgrade on - its too old to support 1.44mb floppies.
I pulled a Compaq computer from the trash. Opened the case and it was built like a tank as well. Some one had took a hammer to the hard disk pins, which I straightened. After reassembly, I booted the machine and everything was on the hard disk ! It was an insurance company with all client data. I did the right thing and reformatted the disk. I also had a Compaq portable. My father-in-law was an IBM executive and was interested in it so i sold it to him.
Geeking out on these old school computers and retro repairs very well made not many have the knowledge and skill anymore
If I remember correctly the 401 error for the Compaq usually meant open port. If you had a parallel or a serial port loopback connector you could test if I am right or not. I was a Compaq repair tech back then. There were loopback connectors for the serial (RS232, 9 and 32 pin)port, power connector port, parallel port, BNC port (network card testing) and others for testing purposes.
@Adrian's Digital Basement
The Bios code 401 means: Parallel port 1 address assignment conflict
Love this series on the Compaq. I wanted a Deskpro so much when they first came out. I tested my wife's patience drooling over one at the local Compaq shop. Couldn't afford one and settled for a cheaper IBM clone. At least I was able to use one at work every now and then.
Thanks for the great video! BTW, INT 21 / INT 20 sequence is a bit redundant :) As I remember, DOS (especially 2.0+) has a bunch of ways to exit a program: INT 20, RET (which jumps to INT 20), INT 21 with AH = 0, INT 21 with AH = 4C and AL = (recommended) and a couple of others like terminate-and-stay-resident function or short jump to address 0 in COM-file (which again does INT 20). So the actual exit from the program in the video is caused by INT 21 with AH set to 0 implicitly by DOS before the program entry.
Back in the days when I was a kid my first PC programming experience was writing short assembly programs in DEBUG utility because I had a trouble with floppy disk when tried to copy BASIC interpreter to my XT clone :)
that's what i was thinking too -- int 21 should be enough if memory serves
Some thoughts about the floppy controller:
- I've counted four tantalum capacitors, replace them
- there is a 10 turn trimmer pot. Turn it in both directions, to clean the contacts in it (count how much you turn it to find the original position, also measure its resistance before and after. Counting the revolutions is not accurate, since you might not notice when you hit the end stop, some trimpot click when you hit the end stop, but most clicks only in one direction.
- if nothing helps, start resoldering it. If it doens't help either, fill the vias with solder, and solder the component pins on both sides. It might be a broken via.
- if this doesn't help either, you have a nice ornament to hang it on the wall :)
Edit: Oh, and Merry Christmas!
Turns out MAME emulates the Compaq Portable and I was able to find a bug in my speed setting program - fixed and reuploaded.
@@adriansdigitalbasement I'll have to go back to the last video so I could RTFM, but I probably could.
The bug, BTW, was I typed "argv[2]" instead of "argv[1]".
Friendly Neighborhood Jesus Freak Ah yes, the classic “wait, what argument has that value?” error
@@AshtonSnapp Heh, yep. Just found the document Adrian was using - didn't realize it was from John Elliott's page. XD
"Friendly Neighborhood Jesus Freak" the best nickname in the history of youtube.
The 401 error means a Parallel port 1 address assignment conflict.
bien adrian saludos de buenos aires argentina👍👍👍👍👍👍👍
The video card looks exactly like the card in the Compaq portable. The CRT on the portable connects to the dual row header above the controller chip. I don't remember what J405 does, but J402 is composite video.
Hey Adrian. I'm new to your channel but I just want to say fairplay for your videos. I had one of these Compaq computers and I can't tell you how many hours of the D&D game Hillsfar I have under my belt. Great memories.
"401 Parallel port 1 address assignment conflict "
"This guy's a little like Santa Claus! "- Alan
Also, DOS memory usage tweaking... ohhhh how delicious that used to be!!
@Adrian Black, would love to watch your deep dive into C=64 or Amiga disk copy protection -- what studios did to their diskettes to protect them from being copied by the end-user's disk drive. I was reading the old Kracker Jax Revealed Trilogy PDF online. Some copy protection methods were quite fascinating. I'm still baffled over the random bit flipping on original disks vs the static bit on copied disks.
Ahh the good old days of upper/extended memory. The amount of time I spent optimising the memory..
The composite video is pretty cool. Thanks for sharing.
I love the sound of floppy drives. So awesome.
if we don't see you before ... have a great xmas and all the best for the new year.
thanks for the videos Adrian and keep up the good work :)
A small anecdotal detail: the Deskpro I had in the early 90s (which was a hand-me-down from my father who bought it new) had two floppies, one in each of the upper bays. The bottom bays had two blanks. From this, I would guess that a configuration with two floppies and an HDD would have had the floppies in the top bays and the HDD in one of the bottom bays. I don't know for sure which one, but the blank bay cover and the hard drive front look the same except for the light, so it doesn't matter much from an aesthetic point of view. When I acquired an HDD later, I put it in the bottom right, but I don't remember 25 years later if there was a particular reason why. Looking at the floppies that came in your box, I would guess it initially had a single floppy and an HDD.
Also... 401 means Unauthorized! Clearly the machine knows you're using a controller card from a different OEM! (kidding-- that's what the 401 HTTP response code means, if you don't know.)
The bottom drive is the same kind of drive used with the FD-502 drive kit for the Color Computer.
I love those old orange screens, now I have watched this I am going to have to buy a vintage PC with an orange screen... Bugger, more expense to satisfy my wants lol. Great video, thanks for sharing...
3:00 Floppy rendition of the Jaws theme?
I absolutely love that screen. Need to find an amber one someday.
reminds me of the gas plasma display on my Toshiba T5200 laptop...
27:15 that chip-on-socket seems to be in 2 parts, maybe the upper part slots in the lower part, that contains the cells...
The mismatched disk drives are interesting. The run lights are in opposite corners.
If I remember correctly dir -w is to list the directory across the width of the screen. It would come in handy for long directory listings.
I guess the C program has the error, that argv[1] should be used instead of argv[2] at the stricmp() calls. Seems to be a typical off-by-one error, because the first element is actually the zeroth element :) EDIT: never mind, just noticed after reloading the page that this is already discussed below :)
I wonder if it is possible to arrange for argv[2] to be pointing at the right string. Say running CPQ SPEED FAST FAST immediately followed by CPQSPEED FAST. I bet DOS safely zeros everything. (BTW: I think this comment was first.)
@@tackline There's a check on argc>2 above which will trigger.
@@galier2 Yeah, I see that, but I suggest running the program twice. First time it does have argv[2] set FAST but doesn't execute. Second time it does execute and but argv[2] is undefined. Hopefully, the memory has been reused without wiping, leading to argv[2] remaining FAST.
That’s a date code label on the top drive. Indicates assembly of PC for service warranty.
It's been a long time, and my memory is sketchy, but what most PC's see as LPT1 is reversed on early Compaq's, try setting the jumpers on your multi-I/O to LPT2 for the onboard parallel port. That is why you are getting the 401, since all Deskpro's shipped with a parallel port.
To add clarity, it's the base address that's reversed.
I have the complete hardware maintenance and service documentation for the original deskpro if you need any information out of it. I also have the technical reference manual for the 386/25 model, but it also covers some of the expansion cards of the earlier models.
Because you released part 3 im watchind Part 1 and 2 in a row hahaha
Composite colour artefacting does work in PAL, but you have to use horizontal lines, rather than vertical. You can also switch the palette using colours of a similar shade at the full 50Hz, which on a CRT(at least a PAL composite one) will result in the 2 colours blending together from beam persistence.
Mayhem in Monsterland(1993) for C64 makes great use of this. A game I would rate as good as any NES game, save maybe Mario 3. Still have my original tape.
There’s something serious about those old amber displays. I grew up with full color Amiga 4096 color goodness. But there was always a side eyed respect for those amber displays like they were for launching nukes and stuff while I was toying around with my color display playing Dungeon Master.
Great video! I have heard that the cracks becomes beacuse the steal dosent shrink but the plastic get smaler with time. but the metal stay the same. and when it shrink they crack becuse the pressure
Battle Chess is another game that has a CGA composite monitor mode - run with /comp on the command line.
The cpqspeed program should be looking at argv[1], not argv[2]. argv[0] is 'cpqspeed' and argv[1] is 'FAST' or 'SLOW'.
You know what they say, there are 3 hard problems in programming: naming things, and off-by-one errors.
I recently had a floppy controller that would just randomly stop working. I spent ages trying to figure out the problem, but eventually gave up. I ended up doing the same thing as you, at least until I can get an 8 bit card. I disabled the game port on mine though, as it seemed to cause a conflict.
Is that board covered in rosin core flux. As the flux dries out the impedance decreases. It's all so much harder to remove. The flux can be causing shorting. You might try soaking it in isopropyl and scrubbing it. Or replacing the ceramic caps.
"Compaq Desktop System Post Messages:
401 Parallel port 1 address assignment conflict"
maybe?
I agree
Maybe there are some dry solder joints on that floppy board. Sometimes these are impossible to see. I would go over with an soldering iron to reflow the solder
They're probably changing pallet data on the card between scanlines. This was a trick sometimes used on the Sega Genesis to get more than 64 colors on screen at a time, and it's very timing critical.
Another great video! Cheers Adrian from New Zealand
The 16bit multi I/O card is so similar to the one on my first PC.
7:35- Don’t worry. I do things like that all the time! You aren’t alone.
4:21 this is a made by "Mitsubishi Electric". not an "Matsushita".
I think it was very unusual for PCs to have an 8086 CPU and 8bit slots, I know a lot certainly had custom expansion slots that were 16bit and directly connected to the CPU. I guess this included some kind of compatibility bridge for 8 bit slots while keeping 16bit memory access.
Interesting. I have a couple other 8086 machines but those are 8-bit slots too ...... I also have a 286 (Tandy 1000TL) that also only has 8-bit slots ... so a total waste LOL. The 8086 is still not great versus a 286 because the data and address bus is still multiplexed on the same pins on the CPU, so you aren't getting that much of a performance increase.
@@adriansdigitalbasement Perhaps it got more common later in the 80s for low end PCs since 8086 CPUs wouldn't have been any real cost saving over the 8088, and PC hardware compatibility was just as important as software by then. A while back I read through loads of old reviews of early 80s PC clones and the 8086 ones were more or less 100% compatible through DOS and the BIOS, but wouldn't work with any 8 bit PC expansions.
I recall that mode bw80 would work on the IBM to switch to mono.
27:50 - take a multimeter to the pins while the battery is still good and find the pins that supply the power to the ROM.
We don't have to worry too much -- that watch chip is a Dallas part and people have made some modern replacements without the potted batteries. :-)
@@adriansdigitalbasement Nice to see they have a solution - I'm well versed in the RTC 1287 battery mod, this would have been an interesting challenge, what with the ROM being on top of the internal battery. :)
www.tindie.com/products/cyberneticsys/tandy-1000-hxsx-smartwatch/ This is the link to the modern version -- it's the DS1216 clock chip. Gotta say a very slick implementation and this works on other computers like the Apple II even. And yes I've mded several of those DS1287 to add the external battery -- a great fix. I will probably one day get around to checking this out since it really isn't working anyway.
absolute genius!
The way the controller card was acting sounded like a possible broken solder joint, but not having a clue where to start, maybe going the easy-route and doing the modern day graphics card repair of baking the card might help re-flow the solder? If it's a lost cause as it is, there's not much to lose, just remember to protect any melty plastic parts with foil to avoid making a mess... :)
Hi there, awesome video. I have a question. I got my hands on an amber monitor but i don't have the compaq. I wonder how i might be able to rig it so it works as a CGA monitor for another computer. Is that realistic? perhaps the resolution is hyper specific to the system it was made for? I thought it would be awesome to hook it up to my Sinclair 1000 or maybe I'll get my hands on CGA PC down the road..
that mem expansion is awesome! I need one
With an old MFM or RLL drive you'll want to park the heads before turning the computer off. IDK if DOS 6.22 has a PARK.EXE program though.
Have you applied some kind of noise gate to your sound recording?
What about the PRIME2C Goldstar LGS Prime 2c Multi I/o Card, What about a Numeric Data Processor, try Settime
32:13 Using DEBUG to create command files to switch processor to fast mode and slow mode.
Terrific video! Nice machine!
Hey, where can we get ahold of the NO-SLOT-CLOCK CLOCK, XTCLOCK and CLKINIT utilities? Been searching for like an hour, and can't turn up anything. I know it's been a couple years, so sorry for the late ask lol
Yes, CGA could support more colors on composite, not that I knew that back in 1988. The 8-bit guy talks about developing for it on one of his games.
yep first drive unit is a version of the cream one in my 1541!
I was looking online. I'm sure you already fixed this but that error 401 refers to a conflicting address with the Parallel Port. Good Luck! Cheers!
Yeah check out Part 3 -- I address that in that video.
@@adriansdigitalbasementI am watching it now. I love old computers. Grew up with a 80386 that my dad bought down here in Klamath Falls. I'm hoping to find a 486 one day. I love messing with DOS and want to learn more. I love your videos!
Speaking of getting cf cards not willing to boot, after fdisk, formating and transferring the system files use the command fdisk /mbr on the cf card. Should fix the boot issue. Works on my Pii machines.
just saw one on ebay but the drives are side by side.
Does anyone know where I can get one of those Wifi Modems used in this video?
There are a lot of them online. Try googling rs232 wifi adapter or sumthing like that!
word. And will it work with say like mid 90's win 3.1 and 95 machines with only a serial port and no modem?
@@timblake5844 No idea.
Thanks Adrian! And also for the great videos. Merry Christmas!!
Thanks, Adrian
so why wait until the summertime to retr0brite the machine? I thought the point of the UV box setup was to be rid of the need to wait for summer to come around before you wanted to de-yellow stuff. wouldn't it be easier to just get a rubbermaid and line it with foil tape and work your magic that way?
I'm not exactly sure why he advised you call int 21, a simple out and then int 20 would have done the trick
As far as I know you can use IDE on this 16-bit multi-function cards in 8-bit slot with CF card and XT-IDE BIOS configured for this (16-bit ISA IDE in 8-bit mode). Never tried this though.
The ISA 16bit controller has two serial ports.The serial port IC is a 8250:. en.wikipedia.org/wiki/8250_UART
19:33: Please be careful with this. It is possible to damage some CGA monitors by treating them as MDA/Hercules, and it is possible to damage some MDA/Hercules monitors by treating them as CGA. Depending on the monitor, doing that can effectively be a killer poke -- see the Wikipedia article -- but yes, I also know this from personal experience.
Who in their right mind would watch a video like this and not like it? I don't get it. I'd give it two thumbs up if I could.
what's with that selfmade "memory card" ? is there a video about it or schematics and stuff ? i'd like to build a ram expansion card for my 5170, but if i can use an already existing design, i would not have to reinvent the weel one more time
One desperation move for the floppy controller is to replace the crystal oscillator. If the machine suffered any physical shock in its life, the crystal could have a fracture and quit working reliably.
The left connector is how the compaq portable plugs into the card
Excellent series. :)
401 Parallel port 1 address assignment conflict
21:00 the colours don't match your description, in the video.
Strange your CPU is soldered but mine is socketed. Maybe they stopped doing the sockets later in the production cycle for cost savings?
Do you not have the serial and printer port dongles for Checkit? They were just plugs with some looped wires I think.
I never ended up having those (or making them.) I probably should I have the parts to do it.
@@adriansdigitalbasement dead link of rom dump compaq deskpro. you can repost the link?
The CPU is also an AMD manufactured, Intel patented processor.
What I'm watching on has a wich is a tablet has a ram issue it won't let me turn on secure folder!?
Ever heard of the Philips NMS9100?
Can you help me the error says close document or apps
I had no idea that debug could produce executables (well, COM files)
I guess it's a legacy from CP/M, upon which MS_DOS was originally modelled...
I found this: thestarman.pcministry.com/asm/debug/debug2.htm#W
which explains a bit about it, but it's not for the novice or the faint-of-heart ;)
I didnt look at the code on the screen, but if it a command line switch, it might a /
The 8 bit guy has recently published a video about using UV lights to do retro brighting.
Jan Beta also uses a UV setup for all of his retrobrighting
And Retro Recipes had one showing that you don't need hydrogen peroxide, although he said that method does require real sunlight.
Try to run the 8088 Domination Demo!
God damn those Panasonic floppy drives. I have two different ones, which both have some fully cracked plastic parts rendering them useless. No such problems with TEAC's.
@@adriansdigitalbasement Jes, let's hope! It's frustrating when old tech fails because of such (I guess) cost saving measures.
I cant help to notice that the intel d8086 chip has a amd logo on it, why do you think that might be.
Hope you can read this, just a quick suggestion, I guess you could try doing what I do to old corroded PCBs, which is using a very soft sandpaper to sand down the connector at the lower part, just quite a bit until you see the metal shinny, as it should be.
brasso works well and a fiberglass pen on the fingers of the PCB.
why would these old putters need a clock anyways. and why go tru the hassle to fix the battery
where do i get one of them modems?
Look into c64 net firmware and grab an esp8266 and a max3232!
I can only find this on the 401: Parallel port 1 address assignment conflict
No vintage screens or PC's on EBAY, damn now my need for one of these is getting desperate!
Funny enough, when the camera focused on your hand, the graphics looked much better
I have don a lot of research for your 401 issue and yes, my friend with same computer (lille different config though) and with 16bit expansion for fdd, has the very same error but the pc worx 100%
Hey, I googled this quite a few times now and wasn't able to find something. Where can I get such an IBM ANSI-file? Also, would this work with the MDA card?
Your help would be very much appreciated. Thanks in advance.
I didn't see any comments on this... but how did you disable the onboard floppy BIOS? I've got a compaq portable that I'm playing with a floppy upgrade on - its too old to support 1.44mb floppies.
Port 401 from Compaq Docs.
Parallel port 1 address assignment conflict... ?!?!?