| I/O | Decoded as | Port | Read | Write | 
| #1C00 | %x0xxxx00 xxxxxxxx | Dk'tronics Lightpen faulty mirror of #BCXX CRTC Index | - | Write | 
| #1F00 | %x0xxxx11 xxxxxxxx | Dk'tronics Lightpen faulty mirror of #BFXX CRTC Data In | Read | - | 
| #78XX | ? | 4Mb Memory extension | - | Write | 
| #79XX | ? | 4Mb Memory extension | - | Write | 
| #7AXX | ? | 4Mb Memory extension | - | Write | 
| #7BXX | ? | 4Mb Memory extension | - | Write | 
| #7CXX | ? | 4Mb Memory extension | - | Write | 
| #7CXX | %0xxxxx00 xxxxxxxx | Aleste 520EX RAM Mapper page 0 (extended "Gate Array 3") | Read | Write | 
| #7DXX | ? | 4Mb Memory extension | - | Write | 
| #7DXX | %0xxxxx01 xxxxxxxx | Aleste 520EX RAM Mapper page 1 (extended "Gate Array 3") | Read | Write | 
| #7EXX | ? | 4Mb Memory extension | - | Write | 
| #7EXX | %0xxxxx10 xxxxxxxx | Aleste 520EX RAM Mapper page 2 (extended "Gate Array 3") | Read | Write | 
| #7FXX | ? | 4Mb Memory extension | - | Write | 
| #7FXX | %0xxxxx11 xxxxxxxx | Aleste 520EX RAM Mapper page 3 (extended "Gate Array 3") | Read | Write | 
| #7FXX | ? | Dk'tronics memory expansion | - | Write | 
| #7FXX | ? | Dobbertin Memory Expansion | - | Write | 
| #7FXX | %01xxxxxx xxxxxxxx | Gate Array | - | Write | 
| #7FXX | %0xxxxxxx xxxxxxxx | PAL extension to Gate Array for 128K RAM banking | - | Write | 
| #BCXX | %x0xxxx00 xxxxxxxx | 6845 CRTC Index | - | Write | 
| #BDXX | %x0xxxx01 xxxxxxxx | 6845 CRTC Data Out | - | Write | 
| #BEXX | %x0xxxx10 xxxxxxxx | 6845 CRTC Status (as far as supported) | Read | - | 
| #BFXX | %x0xxxx11 xxxxxxxx | 6845 CRTC Data In (as far as supported) | Read | - | 
| #DFXX | %xx0xxxxx xxxxxxxx | Upper ROM Bank Number (as decoded within CPC664, CPC6128, 464+, 6128+, decoding in ROM expansions may be different) | - | Write | 
| #ECXX | %xxx0xx00 xxxxxxxx | KC Compact CIO Port B (timer) | Read | Write | 
| #EDXX | %xxx0xx01 xxxxxxxx | KC Compact CIO Port C (timer) | Read | Write | 
| #EEXX | %xxx0xx10 xxxxxxxx | KC Compact CIO Control | Read | Write | 
| #EEXX | %xxx0xxx0 xxxxxxxx | Aleste 520EX USART 8251 (RS232/Mouse) Data | Read | Write | 
| #EFXX | %xxx0xx11 xxxxxxxx | KC Compact CIO Port A (Bi-drectional Printer Port) | Read | Write | 
| #EFXX | %xxx0xxx1 xxxxxxxx | Aleste 520EX USART 8251 (RS232/Mouse) Control/Status | Read | Write | 
| #EFXX | %xxx0xxxx xxxxxxxx | Printer Port | - | Write | 
| #F4XX | %xxxx0x00 xxxxxxxx | 8255 PIO Port A (PSG Data) | Read | Write | 
| #F5XX | %xxxx0x01 xxxxxxxx | 8255 PIO Port B (Vsync,PrnBusy,Tape,etc.) | Read | - | 
| #F6XX | %xxxx0x10 xxxxxxxx | 8255 PIO Port C (KeybRow,Tape,PSG Control) | - | Write | 
| #F7XX | %xxxx0x11 xxxxxxxx | 8255 PIO Control-Register | - | Write | 
| #F8B0 | ? | Vidi-CPC Video-Digitiser | ? | ? | 
| #F8B1 | ? | Vidi-CPC Video-Digitiser | ? | ? | 
| #F8DC | ? | CPCI Serial Interface MC6850 Control/Status | Read | Write | 
| #F8DD | ? | CPCI Serial Interface MC6850 Data | Read | Write | 
| #F8E0 | ? | DHCP MIDI Interface | Read | Write | 
| #F8E0 | ? | Schneider RS232 Interface Z80 STI Indirect Data Register | Read | Write | 
| #F8E1 | ? | Schneider RS232 Interface Z80 STI Gen. Purpose I/O Interrupt | Read | Write | 
| #F8E6 | ? | Port A - IDE8255 | ? | ? | 
| #F8E7 | ? | Port C - IDE8255 | ? | ? | 
| #F8E8 | ? | Schneider RS232 Interface Z80 STI Pointer Vector Register | Read | Write | 
| #F8E8 | ? | Music Machine Interrupt Sel | - | Write | 
| #F8EC | ? | Schneider RS232 Interface Z80 STI USART Control Register | Read | Write | 
| #F8EC | ? | Music Machine ACIA Control | - | Write | 
| #F8ED | ? | Music Machine ACIA Data Write | - | Write | 
| #F8ED | ? | Schneider RS232 Interface Z80 STI Receiver Status Register | Read | Write | 
| #F8EE | ? | Music Machine ACIA Status | Read | - | 
| #F8EE | ? | Schneider RS232 Interface Z80 STI Transmitter Status Register | Read | Write | 
| #F8EF | ? | Schneider RS232 Interface Z80 STI USART Data Register | Read | Write | 
| #F8EF | ? | Music Machine ACIA Data Read | Read | - | 
| #F8E2 - #F8E4 | ? | Dobbertin Eprommer 4003 | ? | ? | 
| #F8F0 | ? | Music Machine DAC Write | - | Write | 
| #F8F2 | ? | EMR MIDI Interface | - | Write | 
| #F8F2 | ? | Dobbertin Eprommer 4003 | ? | ? | 
| #F8F4 | ? | Music Machine ADC Read | Read | - | 
| #F8F8 | ? | Music Machine ADC Start | - | Write | 
| #F8FF | %1111100x 111xxxxx | CPCISA control port | - | Write | 
| #F8FF | N/A | Peripheral Soft Reset (MC_BOOT_PROGRAM and MC_START_PROGRAM do OUT [F8FF],FF) | - | Write | 
| #F9B0 | ? | Vidi-CPC Video-Digitiser | ? | ? | 
| #F9E6 | ? | Port B - IDE8255 | ? | ? | 
| #F9E7 | ? | RS Port - IDE8255 | ? | ? | 
| #F9F7 | ? | Hegotron grafpad II | ? | ? | 
| #F9FC - #F9FE | ? | Otten & Fecht 1 MB RAM-Disc | Read | Write | 
| #F9FF | ? | Hegotron grafpad II | ? | ? | 
| #FA7E | %xxxxx0x0 0xxxxxxx | Floppy Motor Control (for 765 FDC) | - | Write | 
| #FABC | %xxxxx0x0 10xxxx00 | Aleste 520EX EXTPORT with CS53: Forward PPI Port A to 8253 Timer 0 | - | Write | 
| #FABD | %xxxxx0x0 10xxxx01 | Aleste 520EX EXTPORT with CS53: Forward PPI Port A to 8253 Timer 1 | - | Write | 
| #FABE | %xxxxx0x0 10xxxx10 | Aleste 520EX EXTPORT with CS53: Forward PPI Port A to 8253 Timer 2 | - | Write | 
| #FABF | %xxxxx0x0 10xxxx11 | Aleste 520EX EXTPORT with CS53: Forward PPI Port A to 8253 Control | - | Write | 
| #FABF | %xxxxx0x0 10xxxxxx | Aleste 520EX EXTPORT (config for internal hardware) | - | Write | 
| #FADC | ? | Amstrad Serial Interface Z80-SIO / DART port A Data Register | Read | Write | 
| #FADD | ? | Amstrad Serial Interface Z80-SIO / DART port A Control Reg. | Read | Write | 
| #FADE | ? | Amstrad Serial Interface Z80-SIO / DART port B Data Register | Read | Write | 
| #FADF | ? | Amstrad Serial Interface Z80-SIO / DART port B Control Reg. | Read | Write | 
| #FAE6 | ? | Port A - IDE8255 | ? | ? | 
| #FAE7 | ? | Port C - IDE8255 | ? | ? | 
| #FAEE | ? | Amstrad SSA-1 Speech Synthesizer (faulty mirror used by included RSX driver) | Read | Write | 
| #FB7E | %xxxxx0x1 0xxxxxx0 | 765 FDC (internal) Status Register | Read | - | 
| #FB7F | %xxxxx0x1 0xxxxxx1 | 765 FDC (internal) Data Register | Read | Write | 
| #FBBD | ? | Ram select mode Vortex SP512 | ? | Write | 
| #FBDC | ? | Amstrad Serial Interface 8253 Timer counter 0 | Read | Write | 
| #FBDD | ? | Amstrad Serial Interface 8253 Timer counter 1 | Read | Write | 
| #FBDE | ? | Amstrad Serial Interface 8253 Timer counter 2 | Read | Write | 
| #FBDF | ? | Amstrad Serial Interface 8253 Timer Modus Select | - | Write | 
| #FBxx+0 | ? | CPCI Real Time Clock Index (DIY) | - | Write | 
| #FBxx+1 | ? | CPCI Real Time Clock Data (DIY) | Read | Write | 
| #FBE0 - #FBE3 | ? | Dk'tronics Real Time Clock | ? | ? | 
| #FBE0 | ? | Dobbertin Harddisc Data Port | Read | Write | 
| #FBE1 | ? | Dobbertin Harddisc Status, Reset | Read | Write | 
| #FBE2 | ? | Dobbertin Harddisc Select, Configuration | Read | Write | 
| #FBE3 | ? | Dobbertin Harddisc DMA, Interrupt | Read | Write | 
| #FBE4 | ? | Dobbertin Harddisc Reset | Read | Write | 
| #FBE6 | ? | Port B - IDE8255 | ? | ? | 
| #FBE7 | ? | RS Port - IDE8255 | ? | ? | 
| #FBE7 | ? | ACU Real Time Clock (DIY) Z80-PIO Data In/Out Port A | Read | Write | 
| #FBE8 | ? | Dk'tronics Real Time Clock | ? | ? | 
| #FBE8 | ? | KDS RS232 8253 Timer0 (RX Clock) | Read | Write | 
| #FBE9 | ? | KDS RS232 8253 Timer1 (TX Clock) | Read | Write | 
| #FBEA | ? | KDS RS232 8253 Timer2 (not used) | Read | Write | 
| #FBEB | ? | KDS RS232 8253 Timer Control | - | Write | 
| #FBEC | ? | KDS RS232 6850 (reversed bit-order) Control | - | Write | 
| #FBEC | ? | PDS development system Data | ? | ? | 
| #FBED | ? | KDS RS232 6850 (reversed bit-order) TX Data | - | Write | 
| #FBED | ? | PDS development system Handshake | Read | Write | 
| #FBEE | ? | Amstrad SSA-1 Speech Synthesizer | Read | Write | 
| #FBEE | ? | KDS RS232 6850 (reversed bit-order) Status | Read | - | 
| #FBEF | ? | KDS RS232 6850 (reversed bit-order) RX Data | Read | - | 
| #FBEF | ? | ACU Real Time Clock (DIY) Z80-PIO Data In/Out Port B | Read | Write | 
| #FBF0 - #FBFF | ? | Otten & Fecht 1 MB RAM-Disc | Read | Write | 
| #FBF6 | ? | Vortex Disc Drives 765 FDC (Vortex,ext) Status Register | Read | - | 
| #FBF7 | ? | Vortex Disc Drives 765 FDC (Vortex,ext) Data Register | Read | Write | 
| #FBF7 | ? | ACU Real Time Clock (DIY) Z80-PIO Configure Port A | Read | Write | 
| #FBF8 | %11111011 11111000 | 8bit Printer Port (Amstrad Action) Strobe/Busy | Read | Write | 
| #FBF9 | %11111011 11111001 | 8bit Printer Port (Amstrad Action) Data | - | Write | 
| #FBFE | ? | Magnum Light Phaser | - | Write | 
| #FBFE | ? | Dart Scanner for DMP-Printers | Read | ? | 
| #FBFE | ? | Dk'tronics Speech Synthesizer | Read | Write | 
| #FBFE | ? | TMPI speech synthesizer Data Register |  | Write | 
| #FBFF | ? | TMPI speech synthesizer Command/Status Register | Read | Write | 
| #FBFF | ? | ACU Real Time Clock (DIY) Z80-PIO Configure Port B | Read | Write | 
| #FC00 - #FDFF | %1111110x xxxxxxxx | CPCISA 16bits mode high byte latch | Read | Write | 
| #FCE6 | ? | Port A - IDE8255 | Read | Write | 
| #FCE7 | ? | Port C - IDE8255 | Read | Write | 
| #FD00 - #FD3F | %11111101 00xxxxxx | SYMBiFACE II | Read | Write | 
| #FDE6 | ? | Port B - IDE8255 | Read | Write | 
| #FDE7 | ? | RS Port - IDE8255 | Read | Write | 
| #FE00 - #FFFF | %1111111x xxxxxxxx | CPCISA I/O access (low byte) | Read | Write | 
| #FEE6 | ? | Port A - IDE8255 | Read | Write | 
| #FEE7 | ? | Port C - IDE8255 | Read | Write | 
| #FEE8 | ? | Multiface II | ? | ? | 
| #FEEA | ? | Multiface II | ? | ? | 
| #FFXX | %11111111 xxxxxxxx | CPC Booster (XX=#00..#28 are used now) | Read | Write | 
| #FFXX | %11111111 xxxxxxxx | Amdrum (unsigned 8bit DAC) | - | Write | 
| #FFE6 | ? | Port B - IDE8255 | Read | Write | 
| #FFE7 | ? | RS Port - IDE8255 | Read | Write |