NextPort:$FF3B

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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+