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Music Processor
The music processor can be thought of as an independent CPU handling all output to the music/noise ports. The MUZCPU has 4 registers:
| MPC | Like all program counters, points to the next data byte to fetch. |
| MSP | Like a stack pointer, points to return addresses on the stack. |
| DURATION | Loaded at the start of a note, then decremented every 60th of a second. |
| VOICES | A status register that tells which voices (tones) to load with what data. |
The voices status register is shown below. Execution proceeds right-to-left. Make sure that you always have at least one PC incrementing bit or load on.
| INC PC | OUT TONE A | INC PC | OUT TONE B | INC PC | OUT TONE C | OUT VIBRA | OUT VOLN |
[NM:56]
