Legend Of Zelda Theme - real 8bit SID 6581 (test2)

this is a MOS 6581 MIDI interface based on a PIC 18F452 20Mhz,
MOS 6581 and MOS 8580 were the Sound Interface Device of '80s Computer Commodore 64.
in this box the PIC acts as a serial to parallel converter allowing MIDI events elaboration, including at this stage:
NOTE-ON /OFF
Control Change
(osc freq, Envelope Generator, Filters, Pulse Witdh, WaveForm, RingMod, Sync..) for all 3 internal oscillators)

in this video I'm testing 3voices midi song played by guitar pro5. Included a dyamic buffer
it sounds better then 'test1' but not yet perfect , especially when too much events are loaded into PIC's buffer

Category:

Science & Technology

Tags:

• SID
• 6581
• 8580
• legend
• of
• zelda
• pic
• 18f452
• synth
• 8bit
• CCS

[lartti83]

Hi! Can you tie R/W pin to ground if only writing is needed? And use CS to activate the writing process? Can you tell me how you implemented the writing process? And did you use the 20MHz clock as SID's clock source too?

[Jimmy333x2]

@lartti83 Hi! I don't use the RW pin, according to what you said, tie it to ground

about the writing this is the concept : output_low(CS); //Chip select on output_B(Address); //Address Bus output_D(Data); //Data Bus  delay_us(1); //pausa 250 ns a 20mhz output_high(CS); //chip select off delay_us(1);

I'm using a 1Mhz PWM generated by the pic itself

hope to be useful ;)

[MacWii]

Trully Better than your previous test :D

[Jimmy333x2]

@MacWii the power of dynamic FIFO!

nowadays i've written a more optimized alghoritm but i still have to try it on this project.

[lartti83]

@Jimmy333x2 thanks for the answers

[SpeedrThe]

do you have a link to schematics for the interface? I want to buy a 6581 chip, but I don't want to spend all the money on an interface for one.

[technoshamanarchist]

Your MIDI is doing a lot better than mine :) Check out my latest video... there's still a lot more to do :|