Board feature control

	Number	Readable	Writable
Machine ID Register	$00	true	false
Core Version Register	$01	true	false
Next Reset Register	$02	true	true
Machine Type Register	$03	true	true
Config Mapping Register	$04	false	true
Peripheral 1 Register	$05	true	true
Peripheral 2 Register	$06	true	true
CPU Speed Register	$07	true	true
Peripheral 3 Register	$08	true	true
Peripheral 4 Register	$09	true	true
Peripheral 5 Register	$0A	true	true
Joystick I/O Mode	$0B	true	true
Core Version Register (sub minor)	$0E	true	false
Board ID	$0F	true	false
Anti-brick Register	$10	true	true
Video Timing Register	$11	true	true
Layer 2 RAM Page Register	$12	true	true
Layer 2 RAM Shadow Page Register	$13	true	true
Global Transparency Register	$14	true	true
Sprite and Layers System Register	$15	true	true
Layer 2 X Offset Register	$16	true	true
Layer 2 Y Offset Register	$17	true	true
Clip Window Layer 2 Register	$18	true	true
Clip Window Sprites Register	$19	true	true
Clip Window ULA/LoRes Register	$1A	true	true
Clip Window Tilemap Register	$1B	true	true
Clip Window Control Register	$1C	true	true
Active Video Line MSB Register	$1E	true	false
Active Video Line LSB Register	$1F	true	false
Generate Maskable Interrupt	$20	true	true
Video Line Interrupt Control Register	$22	true	true
Video Line Interrupt Value Register	$23	true	true
Reserved	$24	false	false
ULA X Offset Register	$26	true	true
ULA Y Offset Register	$27	true	true
Keymap High Address Register	$28	true	true
Keymap Low Address Register	$29	false	true
Keymap High Data Register	$2A	false	true
Keymap Low Data Register	$2B	false	true
DAC B (left) mirror Register	$2C	true	true
DAC A+D (mono) mirror Register	$2D	true	true
DAC C (right) mirror Register	$2E	true	true
Tilemap Offset X MSB Register	$2F	true	true
Tilemap Offset X LSB Register	$30	true	true
Tilemap Offset Y Register	$31	true	true
LoRes X Offset Register	$32	true	true
LoRes Y Offset Register	$33	true	true
Sprite port-mirror Index Register	$34	true	true
Sprite port-mirror Attribute 0 Register	$35	false	true
Sprite port-mirror Attribute 1 Register	$36	false	true
... further results