Address Map (PC-8801)

Port Writes

Port	Name	Function
0x30
0x31	PC-8001 Emulator	Bit8 - background color Bit7 - background color Bit6 - background color Bit5 - Resolution: 320 × 200 if set, else 640 × 200 Bit4 - Screen drawing: draw if set, else do not draw Bit3 - Color: monochrome if set, else indexed color Bit2 - Memory mapping: map 0x7FFF to RAM if set, else ROM Bit1 - Expansion ROM select: map 0x6000-07FFF ROM to N80/N-BASIC if set, else to extended ROM. Set by default.
0x34
0x35
0x52	Background Color	Sets the background color of the screen. The color is an RGB composite. BLUE ON if bit 3 (mask 0x8) set GREEN ON if bit 4 (mask 0x10) set RED ON if bit 5 (mask 0x20) set
0x53
0x54	Toggle Background/Foreground color components	Toggles background and foreground color components on and off if 8-color mode if bit 8 (mask 0x80) set, target is background color, else foreground if bit 7 (mask 0x40) toggle green component GREEN ON if bits 1,2,3 (0x7) set, else OFF else toggle red and/or blue BLUE ON if bit 1,2,3 set, else OFF RED ON if value written / 8 sets bits 1,2,3, else OFF else if monochrome mode, set foreground color BLUE ON if bit 1 set (mask 0x1) RED ON if bit 2 set (mask 0x2) GREEN ON if bit 3 set (mask 0x4)
0x55-0x5b	Palette Write	Writes to the palette. The index written to is the difference between the port number and 0x54. if port 0x31 bit 6 (0x20) set if bit 7 (mask 0x40) toggle green component GREEN ON if bits 1,2,3 (0x7) set, else OFF else toggle red and/or blue BLUE ON if bit 1,2,3 set, else OFF RED ON if value written / 8 sets bits 1,2,3, else OFF else BLUE ON if bit 1 set (mask 0x1) RED ON if bit 2 set (mask 0x2) GREEN ON if bit 3 set (mask 0x4)
0x5c-0x5f