Interface PCB - Audio from Scratch - Part 10

[@weirdboyjim]

Join us on Discord: discord.gg/jmf6M3z7XS Follow me on Twitter: twitter.com/WeirdBoyJim Support the channel on Patreon: www.patreon.com/JamesSharman

[@graealex]

The "instant delivery" feature from JLCPCB is incredible.

[@weirdboyjim]

I bet you are also impressed I can route a board and solder it in less than 10 minutes! 😅

[@graealex]

@@weirdboyjim Well, I have experience with Eagle and Altium, but I never managed to move my mouse pointer as fast as you do...

[@nevyn]

Man, that step replacing a breadboard with a freshly designed PCBA is so incredibly satisfying to watch!! Pure ASMR :)

[@weirdboyjim]

Couldn't agree more!

[@twobob]

Ah so good. As a musician this is close to my heart. As a programmer even closer, and as a guy who really likes to make random amazing things it cupids me like a javelin. Top work mukka

[@weirdboyjim]

Thanks twobox! Glad you are enjoying it!

[@TheRealBobHickman]

Good stuff as usual. I'm sure I'm not the only one that holds my breath as you're placing the components down :P

[@weirdboyjim]

You and me both! Although big breath hold is powering on after I've added something new!

[@churchers]

Those dual channel audio boards are a work of art

[@weirdboyjim]

Thanks Matt! I'm glad I added those volume led's!

[@drivers99]

Omg new audio from scratch video

[@weirdboyjim]

Hope it doesn't disappoint.

[@bonio55]

🙂 Love this series and channel overall and look forward each of your videos as they come out, reading through some of the other comments its such a great community and following on here and find your approch and vide production spot on with process, content and walk through. Keep up the great work and look forward to the next release :-)

[@weirdboyjim]

Thanks! Good to hear you are getting so much out of them. I'll do my best to live up to it!

[@ANormalLuser]

LOVE this work! I really want some audio to go with my breadboard 6502 but I don't want to use out of production chips. I've been thinking of the most simple way to get 3 square and a noise channel and your Audio From Scratch videos just might make it possible for me. Thanks!

[@weirdboyjim]

Glad you are finding it interesting! adding a noise channel shouldn't bee too tough, good luck!

[@causeitis]

Lovely! make sure to build something else when this is eventually finished. I love watching your vids! :)

[@weirdboyjim]

I have more plans for projects than I'll ever be able to complete, no risk of running out.

[@causeitis]

@weirdboyjim love to hear it! Do you have any plans to license a build it yourself kit when this project is done? I would love to build this with my cousin when he's a little older.

[@Philiper83]

Nice work. I had a idea to put a socket for the cristal on the tmp. backplane, so no breadboards. Looking forward to the next one.

[@weirdboyjim]

I had the same idea after I ordered it!

[@martandrmc]

Yay another video!

[@weirdboyjim]

Hope you like it!

[@Otakutaru]

YES!!!! SOLDER IT!!!! 🤤

[@weirdboyjim]

The reflow process still feels like magic to me!

[@FrankGevaerts]

I've been looking forward to this! I want to build a version for RC2014, and the schematics will help a lot with that.

[@weirdboyjim]

Good luck Frank! I'll be dipping into this series from time to time, it's not a high priority though.

[@m1geo]

Nice one James!

[@weirdboyjim]

Thanks George.

[@DamianReloaded]

Thats really nice. Kudos!

[@weirdboyjim]

Thanks a lot!

[@al_lazy3519]

Very cool video! If you're worried about the solder paste getting old I've read a good solution is to mix fresh flux into it. Can't say I've tried that firsthand since my designs are still limited to stripboard

[@weirdboyjim]

I've seen that as well, but easier said than done when it comes in a syringe type dispenser.

[@Fox-Tech]

I fell you about the shaky hands, as I have the same issue when it comes to small parts. Worse it seems that the force needed to use the tweezers just makes it worse.

[@weirdboyjim]

I find little things like sleep quality the night before has a big influence

[@Otakutaru]

I don't think that a shared crystal was really the best choice. Those are really different modules, and by interconnecting them you loose that modularity. What if you want to stop using UART at some point? (Maybe create your own bytecode and runtime so that you can code inside the machine)

[@bonio55]

Agree that a seperate clock would allow for more flexability, even if was just to design the ability for each module requiring clocks to maybe have a jumper to switch between a central / bus clock and maybe a external inputed clock for each module its fed to? maybe something thats easy to allow for when designing next backplane?

[@weirdboyjim]

Hmm, I've been looking at a lot of old circuits that do a lot with reusing clock signals. If I had thought about it in advance I would have put a crystal socket on that temporary backplane so it could run it temporarily as a separate module. Would you be happier if I put the crystal for all the peripherals on all the backplane for them?

[@bonio55]

@@weirdboyjim oh im good with whatever route take, just was thinking with where you said about the clocks being shared and common that if ever wanted to change one in future for whatever reason that may be that would just give the flexability to route specific clocks where needed and also from my previous experience with shared clocks that if the devices connected werent individualy buffered / isolated that 1 board / chip attached going bad can sometimes pull the clock line on rare occasions and made diagnosing more lengthy than needed, my above instance was a really odd one not involving a failed chip but turned out to be a instance of the crystal not oscillating properly becuase the caps on it in that batch of boards where so tighty in tune that the crystal wasnt able to establish its initial instabailty to start, and was solved with putting slightly differnt valued load capcitors 1 at 22pf and 1 at 33pf..... odd fix to surgest but went from batch failure going from 15/100 down to 1 in 200. Slightly off topic so sorry for the long reply but just thinking of the size of board and the length of the tracks carrying the clocks that it could be benefit to multiple osillators closer to use like on a specific module may help with reducing crosstalk and interfearance.

[@Otakutaru]

​@@weirdboyjim In hindsight... It's James child, I would let him cook

[@kilianhekhuis]

@@weirdboyjim yeah, on the old 8-bitters the clock drove both the video signal as well as the bus clock, and everything run off of that.

[@halfacanuck]

Excellent work! Tho that multi-step port controller is crying out to be pipelined, a use of your time which I for one feel you wouldn't regret ;)

[@weirdboyjim]

I'm curious what you mean by pipelined here? The 3 byte address, data, data sequence works well and I can't see a way to get more than 8-bytes of data over at a time. I suppose I could have put it in as memory mapped registers like on the vga, but that would have been covering the same ground twice.

[@halfacanuck]

@weirdboyjim I was just kidding. It reminded me of a microcode step counter so I was imagining what a RISC approach might look like ;)

[@renaissanceman5847]

Got a blooper reel ??.. that would be great as a break

[@weirdboyjim]

I thought my videos are entirely blooper real? 😅

[@theboot100]

You legend mate, another video Im glad your back to hand routing, a well routed board is so satisfying to do and look at. Ive blown a few ic's before from getting impatient with new boards, but i guess with a hotplate and stencil you can be a bit more confident theres no shorts. Do you know what the current draw is at now of the whole project? Another great video, cant wait for the next one.

[@weirdboyjim]

Glad you are enjoying it! I'll do a power test again in a few videos when I have a bit more on pcb. I want to try some code variation's as well for that.

[@theboot100]

Great thanks I'm guessing the leds will be drawing most of your current I would love to hear what's next in the pipeline for this project after audio is all done

[@wChris_]

I had an idea for a simple audio driver, which could probably fit this build. Its partially inspired on how trackers generate music commands. Basically you sit in a loop and are processing audio commands from a buffer per channel. Like playing a note or a rest or more complicated like looping a section. After processing every channel you just wait for the next "tick" this could be the tempo of the music. This could lend itself very well to MIDI as that format on how notes are actually played is very similar. It would also challenge the assembly instructions and could improve future big examples with custom music.

[@weirdboyjim]

You could absolutely do something like that. The simplest way to do it for a circuit like this would be to have a fifo queue of register sets with a time index attached.

[@wChris_]

@@weirdboyjim Im actually talking about a software solution, not a hardware solution. Although having this implemented in hardware would be really cool, considering your processor doesnt have any interrupts, it would be really cool if it could play nice audio in addition to games.

[@ArneChristianRosenfeldt]

@@wChris_how do you get from notes to samples? A queue in RAM like a tracker on PC? Or do you mean the way they work on Amiga? Hardware for wavetables. Or DSP like on SNES?

[@DavidLatham-productiondave]

Fantasic!

[@weirdboyjim]

Thanks David!

[@evisluE]

So the audio was garbled becuase it wasn't in sync?

[@weirdboyjim]

What bit are you referring too? Once I plugged the PCB in it was just some hook up errors.

[@evisluE]

@@weirdboyjim you had some sort of sync module to sync the audio with the rest computer

[@renaissanceman5847]

interesting that you decided to go with the hot plate rather than the hot air... why so?

[@weirdboyjim]

The hot plate is getting more consistent results, I'm also worried about temperature control. The hot air can overheat things easily. Ideally I'd be using a reflow oven but It's really tough to get good footage of the solder flow.

[@renaissanceman5847]

@@weirdboyjim excellent explanation of the hot air issue, thx!.

[@mikafoxx2717]

We need some final fantasy songs like Big Whale in here, its a midi and might sound familiar if you've seen bisqwit's OPL3 MIDI player project

[@weirdboyjim]

I need to spend some time experimenting with the different sounds I can get out of it. For instruments I can only really tweak the ADSR envelope, I have a need to see what I can do in terms of percussion.

[@gawkersdeathrattle1759]

KZbin does weird stuff. I'm seeing posts here from a month ago, but youtube claims it was only released a minute ago.

[@weirdboyjim]

It was unlisted until today.

[@gawkersdeathrattle1759]

@@weirdboyjim Ahh, that'd explain it. Good to see you back!

[@bobweiram6321]

You would make a great actor in a Harry Potter movie.

[@weirdboyjim]

It all started when a visitor told me “Yer a Coder James, ‘an’ a thumpin’ good’un, I’d sat, once yeh’ve been trained up a bit.”

[@OscarSommerbo]

Yay!!

[@weirdboyjim]

Woo!

[@frognik79]

Needs more Megalovania.

[@weirdboyjim]

I'm not sure if my Audio circuit is worth!