Difference between revisions of "Signals"

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*A22I,A23I: A22 and A23 modified for [[68k vector table]] swap
 
*A22I,A23I: A22 and A23 modified for [[68k vector table]] swap
 
*AS: 68k Address Strobe
 
*AS: 68k Address Strobe
 +
*BNK0~2: [[Memory card]] bank selection
 
*CA4: C ROM A4
 
*CA4: C ROM A4
 
*CR0~CR31: [[C ROM]]s data bus (2*16bits), holds data for one 8 pixels line
 
*CR0~CR31: [[C ROM]]s data bus (2*16bits), holds data for one 8 pixels line

Revision as of 03:55, 14 August 2012

  • 6M, 12M, 24M: 6MHz, 12MHz, and 24MHz clock signals
  • 2H1: S ROM A3
  • 4MB: 4MHz inverted
  • A1~A23: 68k address bus
  • A22I,A23I: A22 and A23 modified for 68k vector table swap
  • AS: 68k Address Strobe
  • BNK0~2: Memory card bank selection
  • CA4: C ROM A4
  • CR0~CR31: C ROMs data bus (2*16bits), holds data for one 8 pixels line
  • D0~D15: 68k data bus
  • /DTACK: 68k Data Transmit ACKnowledge
  • FIXD0~FIXD7: S ROM data bus
  • P0~P23: C ROM, S ROM and LO ROM address/data bus (multiplexed)
  • PCK1B: Clock to latch C ROM address from P0~P23 (mapping) on rising edge
  • PCK2B: Clock to latch S ROM address from P0~P15 (mapping) on rising edge
  • /PORTADRS: $200000-$2FFFFF (P2+ ROM/Security chip) any access
  • /PORTOEL: $200000-$2FFFFF (P2+ ROM/Security chip) odd byte read
  • /PORTOEU: $200000-$2FFFFF (P2+ ROM/Security chip) even byte read
  • /PORTWEL: $200000-$2FFFFF (P2+ ROM/Security chip) odd byte write
  • /PORTWEU: $200000-$2FFFFF (P2+ ROM/Security chip) even byte write
  • /PWAIT0, /PWAIT1: adds 0 to 3 cycle delay for P2 ROM reads
  • R/W: 68k Read/Write
  • /ROMOE: $000000-$0FFFFF (P1 ROM) read
  • /ROMOEL: $000000-$0FFFFF (P1 ROM) odd byte read
  • /ROMOEU: $000000-$0FFFFF (P1 ROM) even byte read
  • /ROMWAIT: add 1-cycle delay for P1 ROM reads
  • /SROMOE: $C00000-$CFFFFF (BIOS) read
  • /SROMOEL: $C00000-$CFFFFF (BIOS) odd byte read
  • /SROMOEU: $C00000-$CFFFFF (BIOS) even byte read
  • SDA0~SDA15 : Z80 address bus
  • SDD0~SDD7: Z80 data bus
  • SDRAD0~SDRAD7: ADPCM-A ROM multiplexed bus (data/address)
  • SDRA8,SDRA9,SDRA20~SDRA23: ADPCM-A ROM address bus
  • SDPAD0~SDPAD7: ADPCM-B ROM multiplexed bus (data/address)
  • SDPA8,SDPA9,SDPA10,SDPA11: ADPCM-B ROM address bus
  • SYSTEM: low when onboard ROMs selected
  • SYSTEMB: inverted SYSTEM
  • PA0~PA11: Palette RAM address bus