AMD Geode LX 800@0.9W - Manual (Page 349)

AMD Geode™ LX Processors Data Book 349
Display Controller Register Descriptions 33234H
6.6.12.5 DC Interrupt (DC_IRQ)
DC_CLR_KEY_Y Bit Descriptions
Bit Name Description
31:27 RSVD Reserved. Set to 0.
26:16 CLR_KEY_Y_
END Color Key Vertical End. This field represents the vertical end position of the color key
region minus 1. This represents the first line past the end of the color key region.
15:11 RSVD Reserved. Set to 0.
10:0 CLR_KEY_Y_
START Color Key Vertical Start. This field represents the vertical start position of the color key
region minus 1. This represents the first line within the color key region.
DC Memory Offset 0C8h
Type
R/W
Reset Value 00000003h
DC_IRQ Register Map
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RSVD
VIP_VSYNC_L
O
SS_IRQ
IRQ
RSVD
VIP_VSYNC_
LO
SS_IRQ_MASK
IR
Q
_
MASK
DC_IRQ Bit Descriptions
Bit Name Description
31:18 RSVD Reserved. Set to 0.
17 VIP_VSYNC_
LOSS_IRQ VIP VSYNC Loss IRQ. If set to 1, this field indicates that while GenLock was enabled,
GenLock timeout was enabled, and the DC reached the end of a frame and detected
VIP_VIDEO_OK (DC Memory Offset D4h[23]) inactive. As a result of this condition, the
DC began display of a field/frame based on its own timings.
16 IRQ IRQ Status. If set to 1, this field indicates that the vertical counter has reached the value
set in the IRQ/Filter Control Register. The state of the IRQ_MASK, bit 0, will not prevent
this bit from being set. To clear the interrupt, write a 1 to this bit.
15:2 RSVD Reserved. Set to 0.
1 VIP_VSYNC_
LOSS_IRQ_
MASK VIP VSYNC Loss IRQ Mask. Masks generation of an interrupt in the event that the DC
reaches the end of a frame with GenLock enabled and GenLock timeout enabled and
determines that the VIP_VIDEO_OK (DC Memory Offset D4h[23]) input is inactive.
0 IRQ_MASK IRQ Mask. Setting this bit to 1 prevents the Display Controller from generating an inter-
rupt signal when the vertical counter reaches the value programmed in
DC_IRQ_FILT_CTL (DC Memory Offset 094h). Clearing this bit disables interrupt gener-
ation, but will NOT prevent IRQ, bit 16, from being set.