Semantic search
Number | Readable | Writable | Description | |
---|---|---|---|---|
Layer 2 X Offset Register | $16 | Yes | Yes | Sets the pixel offset used for drawing Layer 2 graphics on the screen. |
Layer 2 Y Offset Register | $17 | Yes | Yes | Sets the Y offset used when drawing Layer 2 graphics on the screen. |
Clip Window Layer 2 Register | $18 | Yes | Yes | Sets and reads clip-window for Layer 2. |
Clip Window Sprites Register | $19 | Yes | Yes | Sets and reads clip-window for Sprites |
Clip Window ULA/LoRes Register | $1A | Yes | Yes | Sets and reads clip-window for ULA/LoRes layer. |
Clip Window Tilemap Register | $1B | Yes | Yes | Sets and reads clip-window for Tilemap. |
Clip Window Control Register | $1C | Yes | Yes | Controls (resets) the clip-window registers indices. |
Active Video Line MSB Register | $1E | Yes | No | Holds the MSB (only, as bit 0) of the raster line currently being drawn. |
Active Video Line LSB Register | $1F | Yes | No | Holds the eight LSBs of the raster line currently being drawn. |
Video Line Interrupt Control Register | $22 | Yes | Yes | Controls the timing of raster interrupts and the ULA frame interrupt. |
Video Line Interrupt Value Register | $23 | Yes | Yes | Holds the eight LSBs of the line on which a raster interrupt should occur. |
ULA X Offset Register | $26 | Yes | Yes | Pixel X offset (0..255) to use when drawing ULA Layer. |
ULA Y Offset Register | $27 | Yes | Yes | Pixel Y offset (0..191) to use when drawing ULA Layer. |
Keymap High Address Register | $28 | Yes | Yes | PS/2 Keymap address MSB, read (pending) first byte of palette colour |
Keymap Low Address Register | $29 | No | Yes | PS/2 Keymap address LSB. |
Keymap High Data Register | $2A | No | Yes | High data to PS/2 Keymap (MSB of data in bit 0) |
Keymap Low Data Register | $2B | No | Yes | Low eight LSBs of PS/2 Keymap data. |
DAC B (left) mirror Register | $2C | Yes | Yes | DAC B mirror, read current I2S left MSB |
DAC A+D (mono) mirror Register | $2D | Yes | Yes | SpecDrum port 0xDF / DAC A+D mirror, read current I2S LSB |
DAC C (right) mirror Register | $2E | Yes | Yes | DAC C mirror, read current I2S right MSB |