Signals: Difference between revisions
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*FIXD0~FIXD7: S ROM data bus | *FIXD0~FIXD7: S ROM data bus | ||
*P0~P23: C ROM, [[S ROM]] and [[LO ROM]] address/data bus (multiplexed) | *P0~P23: C ROM, [[S ROM]] and [[LO ROM]] address/data bus (multiplexed) | ||
*PA0~PA11: [[Palette RAM]] address bus | |||
*PAL: Palette RAM address decode | |||
*PCK1B: Low 55ns, high 610 (1.5MHz) Clock to latch C ROM address from P0~P23 ([[NEO-273|mapping]]) on rising edge. Delayed with capacitor. | *PCK1B: Low 55ns, high 610 (1.5MHz) Clock to latch C ROM address from P0~P23 ([[NEO-273|mapping]]) on rising edge. Delayed with capacitor. | ||
*PCK2B: Low 55ns, high 610 (1.5MHz) Clock to latch S ROM address from P0~P15 ([[NEO-273|mapping]]) on rising edge. Delayed with capacitor. | *PCK2B: Low 55ns, high 610 (1.5MHz) Clock to latch S ROM address from P0~P15 ([[NEO-273|mapping]]) on rising edge. Delayed with capacitor. | ||
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*SYSTEM: low when onboard ROMs selected | *SYSTEM: low when onboard ROMs selected | ||
*SYSTEMB: inverted SYSTEM | *SYSTEMB: inverted SYSTEM | ||
[[Category:Chips]] | [[Category:Chips]] |
Revision as of 06:57, 26 December 2013
- 24M: 24MHz master clock signal
- 12M: 12MHz clock (24/2) non-inverted from NEO-D0
- 8M: 8MHz clock (24/3) non-inverted from LSPC
- 6MB: 6MHz clock (24/4) inverted from NEO-D0
- 4M: 4MHz clock (24/6) non-inverted from LSPC
- 4MB: 4MHz clock (24/6) inverted from LSPC+AS04
- 1MB: 3MHz clock (24/8) inverted from NEO-D0
- 68KCLK: 12MHz clock (24/2) non-inverted from NEO-D0 (equivalent to 12M)
- 68KCLKB: 12MHz clock (24/2) inverted from NEO-D0
- 2H1: S ROM A3
- 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
- C* or 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)
- PA0~PA11: Palette RAM address bus
- PAL: Palette RAM address decode
- PCK1B: Low 55ns, high 610 (1.5MHz) Clock to latch C ROM address from P0~P23 (mapping) on rising edge. Delayed with capacitor.
- PCK2B: Low 55ns, high 610 (1.5MHz) Clock to latch S ROM address from P0~P15 (mapping) on rising edge. Delayed with capacitor.
- /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