Difference between revisions of "ULA Control Port"
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− | Reading the port with certain particular high bytes will read the keyboard | + | Reading the port with certain particular high bytes will read the keyboard - see {{PortNo|$**FE}}. Bit 6 of the ULA byte is always the EAR input. |
Revision as of 15:53, 29 August 2017
Number | $xxFE |
---|---|
Decimal | |
Short desc. | Controls border color and base Spectrum audio settings. |
Bit Mask | %---- ---- ---- ---0 |
Readable | No |
Writable | Yes |
Subsystem |
When written to, adjusts the border color and audio devices as follows:
Bit | Function |
---|---|
0-2 | Border color |
3 | Enable MIC output |
4 | Enable EAR output |
5-7 | Unused |
Reading the port with certain particular high bytes will read the keyboard - see Keyboard ($**FE / 254). Bit 6 of the ULA byte is always the EAR input.