These registers are accessed using the mtpr and mfpr instructions.

• Stack Registers

  • KSP 0x0
  • ESP 0x1
  • SSP 0x2
  • USP 0x3
  • ISP 0x4

• Virtual Memory Registers

  • P0BR 0x8
  • P0LR 0x9
  • P1BR 0xA
  • P1LR 0xB
  • SBR 0xC
  • SLR 0xD
  • MAPEN 0x38

• Process Control Block

  • PCBB 0x10

• Interrupt Handling

  • SCBB 0x11
  • IPLR 0x12
  • ASTR 0x13
  • SIRR 0x14
  • SISR 0x15

• Clocks

  • ICCS 0x18
  • NICR 0x19
  • ICR 0x1A
  • TODR 0x1B

• Console Registers

  • RXCS 0x20
  • RXDB 0x21
  • TXCS 0x22
  • TXDB 0x23

• MacVAX

  • MVCR 0x29
  • MVCS 0x2A
  • MVPID 0x2B
  • MVMEM 0x2C
  • KFP 0x32
  • EFP 0x33
  • SFP 0x34
  • UFP 0x35
  • IFP 0x36

• Machine Check

  • MCSR 0x17
  • MCESR 0x26