GP0 - Rendering Commands
note
This page is mostly intended as encoding reference - for more information about behaviour consult psx-spx.
Commands have an opcode defined in bits 29..32 of the first packet:
| Opcode | Name | Alias |
|---|---|---|
0x0 | Misc | |
0x1 | Polygon | |
0x2 | Line | |
0x3 | Rectangle | |
0x4 | VRAM to VRAM blit | |
0x5 | CPU to VRAM blit | GP0(A0) |
0x6 | VRAM to CPU blit | GP0(C0) |
0x7 | Environment |
0x00 - Misc
Misc commands have another opcode defined in bits 24..29 of the first packet:
| Misc Opcode | Name | Alias |
|---|---|---|
0x00 | NOP | GP0(00) |
0x01 | Clear Cache | GP0(01) |
0x02 | Quick Rect Fill | GP0(02) |
0x03 | Unknown* | GP0(03) |
0x04..0x1E | NOP | |
0x1F | Interrupt Request | GP0(1F) |
* Takes space in the FIFO, but seems like a NOP otherwise
0x07 - Environment
Environment commands have another opcode defined in bits 24..29 of the first packet:
| Environment Opcode | Name | Alias |
|---|---|---|
0x00 | NOP | GP0(E0) |
0x01 | Drawing Settings | GP0(E1) |
0x02 | Texture Settings | GP0(E2) |
0x03 | Set Drawing Area Top-Left | GP0(E3) |
0x04 | Set Drawing Area Bottom-Right | GP0(E4) |
0x05 | Set Drawing Offset | GP0(E5) |
0x06 | Mask Settings | GP0(E6) |
0x07..=0x1F | NOP | GP0(E7)..=GP0(FF) |