Texas Instruments TMS320C64x DSP Benutzerhandbuch

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Video Capture Registers
3-67
Video Capture Port
SPRU629
3.13.9 Video Capture Channel x Event Count Register (VCAEVTCT, VCBEVTCT)
The video capture channel x event count register (VCAEVTCT, VCBEVTCT)
is programmed with the number of DMA events to be generated for each
capture field. VCxEVTCT is shown in Figure 3–37 and described in
Table 3–22.
An event counter tracks how many events have been generated and indicates
which threshold value (VCTHRLD1 or VCTHRLD2 in VCxTHRLD) to use in
event generation and in the outgoing data counter. Once the CAPEVTCTn
number of events have been generated, the DMA logic switches to the other
threshold value. See section 2.3.1.
Figure 3–37. Video Capture Channel x Event Count Register (VCAEVTCT, VCBEVTCT)
31
28
27
16
Reserved
CAPEVTCT2
R-0
R/W-0
15
12
11
0
Reserved
CAPEVTCT1
R-0
R/W-0
Legend: R = Read only; R/W = Read/Write; -n = value after reset
Table 3–22. Video Capture Channel x Event Count Register (VCxEVTCT) Field Descriptions
Description
Bit
field
symval
Value
BT.656 or Y/C Mode
Raw Data Mode
TSI Mode
31–28
Reserved
0
Reserved. The reserved bit location is always read as 0. A
value written to this field has no effect.
27–16
CAPEVTCT2
OF(value)
0–FFFh
Number of DMA event
sets (YEVT, CbEVT,
CrEVT) to be generated
for field 2 capture.
Not used.
Not used.
15–12
Reserved
0
Reserved. The reserved bit location is always read as 0. A
value written to this field has no effect.
11–0
CAPEVTCT1
OF(value)
0–FFFh
Number of DMA event
sets (YEVT, CbEVT,
CrEVT) to be generated
for field 1 capture.
Not used.
Not used.
† For CSL implementation, use the notation VP_VCxEVTCT_CAPEVTCTn_symval