Integrated Functions (Continued)
Table 4-24. Graphics Pipeline Configuration Registers (Continued)
Bit
Name
Description
1
PB (RO)
Pipeline Busy (Read Only): Indicates that the graphics pipeline is processing data.
The “Pipeline Busy” bit differs from the “BLT Busy” bit in that the former only indicates that the graphics pipe-
line is processing data. The “BLT Busy” bit also indicates that the memory controller has not yet processed
all of the requests for the current operation.
The “Pipeline Busy” bit must be clear before loading a BLT buffer if the previous BLT operation used the
same BLT buffer.
0
BB (RO)
BLT Busy (Read Only): Indicates that a BLT / vector operation is in progress.
The “BLT Busy” bit must be clear before accessing the frame buffer directly.
GX_BASE+8210h-8213h
GP_VGA_BASE (R/W)
Default Value = xxxxxxxxh
Note that the registers at GX_BASE+8210h is located in the area designated for the graphics pipeline but is used for VGA emulation
purposes. Refer to Table 4-39 on page 165 for this register’s bit formats.
GX_BASE+8214h-8217h
GP_VGA_LATCH Register (R/W)
Default Value = xxxxxxxxh
Note that the registers at GX_BASE+8214h is located in the area designated for the graphics pipeline but is used for VGA emulation
purposes. Refer to Table 4-39 on page 165 for this register’s bit formats.
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