Positron16 - Commodore 64 SID chip emulator using a dsPIC33 or PIC24 device

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Here is a video I made of the SID sound chip emulator I created, running on a dsPIC33 device, and it sounds excellent. The code also emulates the old, 8-bit, 6502 microprocessor, so it can run the contents of a SID file as if it is running in a Commodore 64 machine.

You will need to forgive me for my commenting in the video, as I am not used to talking on videos, and users from the UK will recognise my Geordie accent, even after all of the years away from the North East of England it still stays in my voice. :-) The phone seems to try to mask out the sound of the SID emulator, because it was actually quite loud, but it can still be heard. It is running on one of my old Amicus24 boards, but it runs nicely on John's Amicus16 board as well.

I am going to try and commercialise it somehow, with a PCB and the source codes and the "SID file to include file" creator program, and a booklet on how to build the PCB, and what the program is doing, and how to use it in applications, and a free compiler version that includes the dsPIC33 device that I will eventually use in it etc... It would make an excellent door bell for us nerds from the 1980s. :-)

Notice the lovely Philips speaker from one of my 1960s electronics sets? It was the only speaker I could find. LOL.

I have attached a hex file for the player that will run on a dsPIC33FJ128GP802, and uses pin 'RP8' for the audio out. The dsPIC33 device uses its internal oscillator, so all that is required is power to the dsPIC device, and the 'RP8' pin connected to an amplifier to hear the theme tune from the 1980s Commodore 64 game called "1942". You can add a 47nF to 100nF capacitor connected from the 'RP8' pin to ground and it will operate as a very simple low-pass filter, or use an op-amp as an integrator/ low pass filter for a bit better quality, but the 10-bit PWM gives a good sound, and I will be converting it to 16-bit using two OC (Output Compare) peripherals operating as high frequency 8-bit PWMs, combined to give a really good 16-bit DAC.

[CPR]

Great job! 

[JonW]

1942 tune brought back some memories.  I was always a C64 over the spectrum in those days and progressed to the Amiga.

Really nice job Les!

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I originally started with a ZX81, bought from WH Smiths, then moved up to a Spectrum. I then got bored with the Spectrum when I had learned enough Z80 code and moved to the "beautiful" Atari 800, with its cast aluminium innards and lovely casing and keyboard. With the wonderful 810 disk drive. Ohhh how I wished I had kept them, they were so beautiful. :-(

I then moved on to the commodore 64 when I heard its SID chip sounds, then the Atari ST. I dabbled with the commodore Amiga but could not quite see its charm, so moved on to the boring 286 onwards computers.

The computers now are actually very boring, and "much the same of the same", and lack any charm whatsoever.

That's what first got me interested in PIC microcontrollers. They were a step back to the good old 8-bit days where computers and electronics mixed. But that is now also fading, and the large 'Arm' microcontrollers now are just small computers doing the same of the same with dreadfully bloated languages and copy and pasting. They are also loosing their charm.