BX first DAC register to read (0-00ffH)
CX number of registers to read (0-00ffH)
ES:DX addr of a buffer to hold R,G,B values (CX*3 bytes long)
Returns: ES:DX buffer contains returned data
Info: This obtains the current 18-bit RGB values of a consecutive block
On entry, the buffer at ES:DX must be large enough to hold the
requested data. Each register takes 3 bytes, so the buffer must
On return, the table is laid out as Red,Green,Blue,
Red,Green,Blue, ... etc. Only the low-order 6 bits of each byte
values for DAC color registers.
16- or 64-register blocks.