dss-088
DAC TEST registers:
Video Encoder Module
VENC_OUTPUT_CONTROL[5] LUMA_SOURCE for DAC1
or
VENC_OUTPUT_CONTROL[7] CHROMA_SOURCE for DAC2
VENC_OUTPUT_CONTROL[4]
TEST_MODE
VENC_OUTPUT_CONTROL[25:16]
LUMA_TEST (DAC1) or
VENC_OUTPUT_TEST[25:16]
CHROMA_TEST (DAC2)
RGB[23:0]
Y[9:0]
(DAC1)
C[9:0]
(DAC2)
DAC[9:0]
RGB[9:0]
0
1
0
1
Public Version
Display Subsystem Functional Description
www.ti.com
Figure 7-115. DAC Test Mode in Separate video Mode
•
Use the DSS.
[4] TEST_MODE bit to select between DAC normal mode
(0x0) and DAC test mode (0x1).
•
Use the DSS.
[7] CHROMA_SOURCE bit for AVDAC2 and either the
DSS.
[6] COMPOSITE_SOURCE bit (in composite video mode) or the
DSS.
[5] LUMA_SOURCE bit (in s-video mode) for AVDAC1 to select the
test mode:
–
0x0: From the internal register DSS.
[25:16] CHROMA_TEST bit field for
AVDAC2 and either DSS.
[9:0] COMPOSITE_TEST bit field (composite
video) or DSS.
[25:16] LUMA_TEST (s-video mode) for AVDAC1
–
0x1: From the video port G[1:0], B[7:0]
NOTE:
In the external data test mode (bypass mode), the display controller must provide the data
(G[1:0], B[7:0]) externally. To do this, configure the video encoder to generate correct timing
signals, without which the display controller cannot operate (even if the encoder core is
bypassed from the data path perspective).
7.4.7.12 Video DAC Stage Power Management
After device reset, the
[5] DAC_POWERDN_BGZ register bit is set to 0, and the video
DAC stage is powered down.
shows possible power management configurations and the corresponding register settings.
1704
Display Subsystem
SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated