NextPort:$FF3B: Difference between revisions
From SpecNext Wiki
No edit summary |
No edit summary |
||
| (One intermediate revision by the same user not shown) | |||
| Line 5: | Line 5: | ||
|Writable=Yes | |Writable=Yes | ||
}} | }} | ||
For ULA+ i/o ports, all colours are read and written in 8-bit format GGGRRRBB. The 9th blue bit is automatically generated | |||
as the logical OR of the two other blue bits. | |||
(R) | (R) | ||
If palette group is selected, the palette value stored at the current ula+ palette index is returned | If palette group is selected, the palette value stored at the current ula+ palette index is returned | ||
If the mode group is selected, bit 0 = 1 to indicate ULA+ is enabled | If the mode group is selected, bit 0 = 1 to indicate ULA+ is enabled | ||
| Line 14: | Line 18: | ||
If the palette group is selected, a palette value is written to the current ula+ palette index | If the palette group is selected, a palette value is written to the current ula+ palette index | ||
If the mode group is selected, bit 0 = 1 to enable ULA+, 0 to disable ULA+ | If the mode group is selected, bit 0 = 1 to enable ULA+, 0 to disable ULA+ | ||
Latest revision as of 13:56, 21 February 2026
| Port Number | $FF3B |
|---|---|
| Decimal | |
| Short desc. | ULA+ Data |
| Bit Mask | |
| Readable | Yes |
| Writable | Yes |
| Subsystem |
For ULA+ i/o ports, all colours are read and written in 8-bit format GGGRRRBB. The 9th blue bit is automatically generated
as the logical OR of the two other blue bits.
(R)
If palette group is selected, the palette value stored at the current ula+ palette index is returned
If the mode group is selected, bit 0 = 1 to indicate ULA+ is enabled
(W)
If the palette group is selected, a palette value is written to the current ula+ palette index
If the mode group is selected, bit 0 = 1 to enable ULA+, 0 to disable ULA+