I made a music box with some 555 timers and an old RAM chip
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- Опубліковано 19 сер 2024
- It makes music! Well... it makes notes! Well... it makes sounds in a sequence that, if you're feeling generous, could be called a song!
-- Stuff
Chip Assortment Kit (with NE555): amzn.to/3x9cb6I
Tiny DPDT slide switches: amzn.to/3wVl97H
TTL ICs: amzn.to/40WH75c
Assortment of push buttons: amzn.to/4a1A0Mv
BB830 Solderless Breadboards: amzn.to/3TkNPOY
Breadboard kit with components: amzn.to/3MYwfho
Power supply: amzn.to/3uAYxIE
Rigol DS1054Z oscilloscope: amzn.to/43C3v5m
Multimeter: amzn.to/49PUg45
Antistatic mat: amzn.to/49RhcQi
My Wife's Books: amzn.to/47yt9Ji
(Maybe you and/or someone you know will like them!)
I have a tip for improvement. You may build a 4 to 16 demultiplexer. That will take a 4 bit number and output a signal on one of 16 outputs. Then you can use 15 individual resistors, one for each note, and have better control over the tuning.
lol this was the first thing i thought maybe instead of resistors use pots so as to adjust the note on the fly. Amazing vid btw!
No need for individually tuned resistors. Just use the right resistor network.
This shows the importance of the journey, love old school reused, thanks for sharing
I would say a good way to immortalize this project in a smaller space so you could take it off the board, would be to design and solder all this to a smaller PCB.
Plus that's great practice for doing more complicated things.
I love this method you're learning by too. Inspiring really.
This looks like the start of an 8 bit retro sound card! Very cool! 🔊
Bro, this is so underrated! You deserve way more than just 1.16k subs! Also while its not a great instrument, it's still very impressive. I don't know much about circuitry but I'm sure someone in these comments may have a good suggestion. I look forward to seeing more!
nunca pidas disculpas por si lo que estas haciendo suena a musica o no, en definitiva sigue siendo compartir conocimiento, compartir cultura de diferentes maneras, pero cultura igual, gracias por el esfuerzo ❤
Instead of resistors, you should have a potentiometer for each note. That way, you can tune each note by hand
You could even use the small blue trim pots for precision tuning, and use a tuning app on your phone to get the notes just right!
The problem though is that without a 4 to 16 decoder, each resistor affects the others depending if the RAM output is 1 (5v) or 0 (ground, not open circuit)
@@danman32 ah, good point. Luckily, 74154s aren't too expensive
@@natethefighter Don't need any tuning. Just use the right resistors.
That 4 resistors on data bits is reminiscent of half of "Covox Speech Thing" which was basically poor man's DAC from c64/Atari era. You can use that voltage to drive voltage to frequency circuit (can be built also on 555)
i didnt see this in the comments yet, but the ram output drop is consistent with the voltage drop across a diode. which makes sense since its a Light Emitting Diode.
I too was thinking the LED voltage drops were likely the problem. I encountered this with one or two Ben Eater projects
Great job. Congratulations on getting through that.
Man you blew up! congratulations! I guess this is some encouragement to try to upload more regularly lol.
Yeah this one blew up for sure! I've been working on another project which was probably too big for my skill level and it has been taking forever (largely due to waiting for some chips to arrive and then, when they do, realizing I needed another kind of chip and then having to wait for that one, over and over.) I just hope I recorded enough along the way to make a video kind of like this one by the end. 😬 We'll see!
@@bigzaphod I know that pain I just had a power supply fail:( lol it was Jerry rigged anyway. All I ask of you is to remember me when you are famous lol! You’re making great content and i’m certain that that upcoming video will be awesome!
I think you could squeze everything on only 1 or 2 breadboards, there's a lot of space you didn't used.
Keep up the good work. In less than a month, you will invent the mp3 player.
lol
Enjoyed it! And you're building a story around a future product for your backers (I'm sure you'd sell a few "piano toys" after you got the tuning and possibly some tone filtering figured out). Plenty of manufacturers catering to the small project crowd will produce fully assembled boards or kits for you in small or large numbers.
Oh wow, I never even thought of that possibility.
@@bigzaphod I've seen other electronics UA-camrs do that. Might be a fun trinket to have, plus a great motivation for you to work towards a goal and not quit. I have ideas 😇 "Now YOU can make the same strange bigzaphot sounds at home. Rickroll your friends and they won't even know it's a rickroll! It even has the patent pending beep-boop button."
maybe add an analogue lowpass filter on the output?
Use a resistor ladder (similar to the R-2R ladder in a DAC) for generating voltages correlated to tones, then use a linear VCO made of a 555, and a simple ADR circuit for note shaping and then you get it.
The magic values for resistors in the ladder... The ones connected to the key lines are of 300k. The ones connecting the ladder in between are of 1k. The termination resistor to ground is of 17.8k (can be a set of two resistors of 18k and 1.8Meg in parallel). You can add as many stages as you want, and every stage decreases the voltage in a ratio of ≈ 2^(1/12), that is, a semitone. Keys can be digital signals from any IC but if you want to make keypressing notes, you have to use SPDT momentary switches, NC to gnd and NO to Vcc. Push buttons do not work here.
The problem with that idea is it wont produce a musical scale.
Instead it will generate unusable frequencies .
@@mikegLXIVMM No, no, this is not an idea, it is an actual design i did in 2021 as a present for a kid. Because i cannot put any link here (or youtube would remove the whole message), i just uploaded a demo video to my yt channel. Check the video description for more information. Feel free to replicate or modify my design.
@@mariobv947
How many bits does it use? It can't be just 4.
@@mikegLXIVMM Let's say that you need as many bits as notes you want to play, but i wouldn't talk about bits because this DAC is not Binary. In fact the Binary DAC (R-2R) network is just a particular case of an infinite set of DACs including, for instance, decimal DACs. in case you encode the notes as Binary Codes, one must demultiplex or decode before sending the note to the DAC. Let's suppose the memory reads 0101, then the decoder will yield 0000000000100000 to the DAC such as the one i have shown.
The interesting thing about this is that you don't need a bunch of fancy valued resistors or fine tuning every resistor value in the ladder.
you can just use stepper motors and gcode to produce music
I suggest to tune the notes more and transfer this to a permanent board! 😉
I'm wondering if you would have gotten better frequency control using pin 5 on the 555 rather than trying to electrically change the timing resistors
very complicated and there are a lot of parts.
Have you thought of looking at the datasheets for the device's, they will tell you all about the output drive capabilities. Ram chips were never designed to have a high drive capability as the were working at the limits of technology at the time and needed all silicon for the ram function. If you produced better drawings we could probably provide some better solutions. Just a thought. Still a ice video to watch.
I should have mentioned it in this video, but since I had talked about it in prior ones I didn't think to. (Plus I didn't expect this video to suddenly get so many views!) The RAM chip is an SY2112A and the catalog with the data sheet is here: web.archive.org/web/20221113021101if_/archive.6502.org/datasheets/synertek_data_catalog_1981_1982.pdf. I didn't really know how to interpret some of the numbers there when it came to the dimming/driving problem I had, but it wouldn't surprise me if the answer is right in front of my face, tbh.
@@bigzaphod having a quick look at the datasheet the output when high, will be a minimum of 2.4V while sourcing (-Ve) 150uA. It has by the look at it a weak pull-up on the outputs. Normally with logic chips you think of this as fan out, the number of standard Inputs that an output can drive and still be within specification.
I wonder if you could get multiple resistances by using charlieplexing. (The way keyboards work without using bajillions of bits.)
Yes, I'm almost certain this is how 'phones' make multiple 'tones' per key press. Some form of charlieplexing.
I knew about the standard grid way of doing this with buttons, but never heard of Charlieplexing before. That is super clever.
@@bigzaphod yes but charlieplexing is only useful by exploting tristate outputs, hence more suitable for use with MCUs.
Oh my god im crying. Nice!!
I winder if it can be tuned wirh a variable resistor? Or multiple?
I thought about doing that, but I figured I'd probably not be able to properly tune it given my general lack of musical talent, but maybe I should try it anyway!
@@bigzaphod I'm tone deaf too. I tried to find a free phone app that I could put in a desired note and have it tell me when whatever I was playing it was near enough. I wasn't able to find one. This was to tune a programmable sound generator ic I have. I just have to rely on the maths for it. Which is possible because it's a digital device. Your circuit is more akin to a true analogue synthesizer. So cool.
You might want to look into voltage controlled oscillator (vco) circuits next. They use op-amps. Who knows you could be designing the next Moog!
The REAL problem is that your "notes" are completely out of tune... you could have googled for the propper frequencies.
With the current circuit design it's literally impossible to properly tune more than 4 notes.