{|{{Prettytable|width: 700px; font-size: 2em;}}
| ''I/O MapPortMeaningPort''||''Direction''||''Name''||''Description''
|-
| F8E8h(|| Write only)Only || INTERUPT SELINTERUPT_SEL
| Writing 01 to this port disables internal Amstrad interrupts and replaces the IRQ signal from ACIA. Writing 00 restores normality. ''(Unclear how this works exactly - the description sounds as if uses an [[External Interrupt]] (rather than a [[NMI]]), and as if it does somehow disable the CPC's internal 300Hz interrupt?)''
|-
| F8ECh (|| Write only)| ACIA Control| ACIA_Control
| See [[6850 ACIA chip]] for details
|-
| F8EDh (|| Write only)| ACIA Data write| ACIA_Data_write
| See [[6850 ACIA chip]] for details
|-
| F8EEh (|| Read only)| ACIA Status| ACIA_Status
| See [[6850 ACIA chip]] for details
|-
| F8EFh (|| Read only)| ACIA Data read| ACIA_Data_read
| See [[6850 ACIA chip]] for details
|-
| F8F0h (|| Write only)| DAC WRITE| DAC_WRITE
| Data can written to the DAC via this port
|-
| F8F4h (|| Read only)| ADC READ| ADC_READ
| The contents of the A-to-D can be read via this port. Note that the A-to-D must have been startet at least 20uS before this port can be read
|-
| F8F8h| ADC START| Strobe || ADC_START
| Reading or writing to this port will start analogue to digital conversion
|-