103
Appendix: Timing for Camera Link Signals
Case 3: FVAL is Edge-Sensitive and LVAL is Level-Sensitive
In this case, FVAL is edge-sensitive and LVAL is level-sensitive.
•
Start of frame/line is signaled by:
A rising (or falling) edge on FVAL, which signals start of
frame
.
The line is valid when LVAL is active (high or low depending on settings).
•
End of frame is signaled by:
•
The next FVAL valid edge (rising edge when rising-edge sensitive or falling edge when falling-
edge sensitive) occurs.
•
Or when all of the lines have been acquired (as set in the image height settings)
AND
the last
LVAL with valid data is de-asserted (low when high level sensitive or high when low level
sensitive).
•
Line Missing status or a Partial Line Missing error generated:
•
Full Line Missing indicates that the frame is ending early (the next FVAL edge occurs before all
of the lines have been acquired). Partial Line Missing indicates that lines are ending early (in
this case, LVAL is de-asserted before all pixels in a line are captured).
Timing Values for All Cases
The timing values stated in the following table are minimum values only.
(1,0)
(N-1,
0)
t
LI2LV
PB_FVAL
PB_LVAL
PB_DVAL
t
FV2LV
t
FI2FV
t
LV2LI
(1,1)
(N-1,
M)
PB_DATAx
(0,0)
(N,0)
(0,0) (1,0)
(0,1)
(N,M)
Don’t Care
Window Size = N x M
t
FV2DV
t
LV2DV
t
LI2DV
t
DI2LI
t
LLI2DV
t
FV2FV
t
FV2FI
Table 28: Timing Values for All Cases
From
To
Symbol
Case 1
(level)
(
t
cp)
Case 2
(edge)
(
t
cp)
Case 3
(both)
(
t
cp)
FVAL valid
LVAL valid
t
FV2LV
0
b
0
1
FVAL valid
Data valid
c
,
d
t
FV2DV
0
b
16
1
LVAL valid
Data valid
c
,
d
t
LV2DV
0
1
0
LVAL valid
LVAL invalid
t
LV2LI
1
1
1
LVAL invalid
LVAL valid
t
LI2LV
1
1
1
