VGA32 Controller - Color Look-up Tables

Two color look-up tables are available for use with the VGA32 Controller, each of which contain 256 addresses. The two tables form a single contiguous 512 x 32-bit address space:

• CLUT0 – with address range 100h to 17Fh

• CLUT1 – with address range 180h to 1FFh

The color look-up tables can be accessed directly through the Controller's Wishbone Slave interface. Direct access is controlled using bit 11 of the io_ADR_I line. When this bit is High, Wishbone communications are configured to be direct with the active color look-up table.

Each 32-bit data entry in the table is comprised as follows:

• bits 31..24 – unused

• bits 23..16 – Red

• bits 15..8 – Green

• bits 7..0 – Blue