Display Control 1 Register
From SpecNext official Wiki
| Number | $69 |
|---|---|
| Readable | Yes |
| Writable | Yes |
| Short Description | Layer2, ULA shadow, Timex $FF port |
| Bit | Function |
|---|---|
| 7 | Enable the Layer 2 (alias for Layer 2 Access Port ($123B / 4667) bit 1) |
| 6 | Enable ULA shadow (bank 7) display (alias for Memory Paging Control ($7FFD / 32765) bit 3) |
| 5-0 | alias for Timex Sinclair Video Mode Control ($xxFF / 255) bits 5:0 |
ULA shadow screen from Bank 7 has higher priority than Timex modes, setting bit 6 to "1" together with one of the extended Timex graphic modes will result into classic ZX128 ULA mode using Bank 7 data.