Timex Sinclair Video Mode Control
From SpecNext Wiki
| Number | PortNumber::$xxFF |
|---|---|
| Decimal | NumberDec:: |
| Short desc. | ShortDesc::Controls Timex Sinclair video modes and colours in hi-res mode. |
| Bit Mask | PortMask::%---- ---- 1111 1111 |
| Readable | Readable::No |
| Writable | Writable::Yes |
| Subsystem | Subsystem::Enhanced ULA |
| Bit | Function |
|---|---|
| 0-2 | 000=Screen 0. 001=Screen 1. 010=Hi-colour. 110=Hi-res. |
| 3-5 | Sets screen color combination for hi-res mode.
The bit pattern does set INK colour, PAPER colour is deducted as complement value, both colours are of BRIGHT variant. I.e. only some combinations are possible, like White/Black, Yellow/Blue, .. |
| 6 | Disables interrupts. Does the same as DI, but cannot be turned on again with EI. Use with caution! |
| 7 | Used for memory paging on the Timex Sinclair, not relevant on the Next. |
Ped7g (talk) 02:09, December 23, 2018 (UTC): I guess the hi-res colours are still fetched through ULANext palette, i.e. any two colours combination is possible through palette modification of the two colours (for example White/Black are 7/128?).