ULA Control Port
From SpecNext Wiki
| Number | PortNumber::$xxFE |
|---|---|
| Decimal | NumberDec:: |
| Short desc. | ShortDesc::Controls border color and base Spectrum audio settings. |
| Bit Mask | PortMask:: |
| Readable | Readable::No |
| Writable | Writable::Yes |
| Subsystem | Subsystem:: |
When written to, adjusts the border color and audio devices as follows:
| Bit | Function |
|---|---|
| 0-2 | Border color |
| 3 | MIC output (saving via audio jack) |
| 4 | EAR output (connected to internal speaker) |
| 5-7 | Unused |
Reading the port with certain particular high bytes will read the keyboard - see {{#ask: PortNumber::$**FE }} ($**FE{{#ask: PortNumber::$**FE |mainlabel=- |headers=hide |intro= / |?NumberDec#- }}). Bit 6 of the ULA byte is always the EAR input (signal from tape audio jack - also input from Pi digital audio is now mixed in, since 3.0 cores).