This is an old revision of the document!
Output Ports
| Port Number (hex) | Function | Notes |
|---|---|---|
| 0 | Color Register 0 (Right) | |
| 1 | Color Register 1 | |
| 2 | Color Register 2 | |
| 3 | Color Register 3 | |
| 4 | Color Register 0 (Left) | |
| 5 | Color Register 1 | |
| 6 | Color Register 2 | |
| 7 | Color Register 3 | |
| 8 | Low/High Resolution | aka Consumer/Commercial mode (Astrocade only uses Consumer) |
| 9 | Horizontal Color Boundary, Background Color | |
| A | Vertical Blank Register | |
| B | Color Block Transfer | |
| C | Magic Register | |
| D | Interrupt Feedback Register | |
| E | Interrupt Enable and Mode | |
| F | Interrupt Line | |
| 10 | Master Oscillator | |
| 11 | Tone A Frequency | |
| 12 | Tone B Frequency | |
| 13 | Tone C Frequency | |
| 14 | Vibrato/Tremolo Register | |
| 15 | Tone C Volume, Noise Modulation Control | |
| 16 | Tone A Volume, Tone B Volume | |
| 17 | Noise Volume | |
| 18 | Sound Block Transfer | |
| 19 | Expand Register | |
[NM:106, 143]
