User's Manual

Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

3.4. Indirect VGA and Extended VGA Register Indices

Programming an index value into the appropriate SRX, GRX, ARX, or CRX register indirectly accesses

the registers listed in this section. The index and data register address locations are listed in the previous

section. Additional details concerning the indirect access mechanism are provided in the VGA and

Extended VGA Registers Chapter (see SRxx, GRxx, ARxx or CRxx sections).

Table 4. 2D Sequence Registers (3C4h / 3C5h)

Index Sym Description

00h SR00 Sequencer Reset

01h SR01 Clocking Mode

02h SR02 Plane / Map Mask

03h SR03 Character Font

04h SR04 Memory Mode

07h SR07 Horizontal Character Counter Reset

Table 5. 2D Graphics Controller Registers (3CEh / 3CFh)

Index Sym Register Name

00h GR00 Set / Reset

01h GR01 Enable Set / Reset

02h GR02 Color Compare

03h GR03 Data Rotate

04h GR04 Read Plane Select

05h GR05 Graphics Mode

06h GR06 Miscellaneous

07h GR07 Color Don’t Care

08h GR08 Bit Mask

10h GR10 Address Mapping

11h GR11 Page Selector

14:1Fh GR[14:1F] Software Flags