e2v ELIIXA+ 16K CXP COLOR, User Manual

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7.3.7 Rescaler
Feature Name CXP @ R/W Size
bytes
Bit field Description
TriggerRescalerSource 0x08540 RW 4 [31-30] RescalerSize (see Erreur ! Source du
envoi introuvable. )
Bit0:
0: line0 selected for rescaler
1: line1 selected for rescaler
Bit1: Bypass Rescaler
TriggerRescalerMultplier [29-18] mult factor for rescaler function
Rescaler will create "mult" pulse between
input trig
TriggerRescalerDivider [17-6] div factor for rescaler function
Rescaler will take 1 pulse each "div" pulse
TriggerRescalerGranularity [5-4] 0: 1 *20 = 20 ns
1: 4 *20 = 80 ns
2: 16 *20 = 320 ns
3: 256 *20 = 5120 ns
TriggerRescalerAverage [3-1] average trigger delay computed with:
0: 1 previous trigger delay
1: 2 previous trigger delay
2: 4 previous trigger delay
3: 8 previous trigger delay
4: 16 previous trigger delay
5: 32 previous trigger delay
6: 64 previous trigger delay
7: 128 previous trigger delay
TriggerRescalerCountInt 0x08544 RW [31-16] count_int overflow
TriggerRescalerCountIntOverflow [15] count_int counter of rescaler bloc
count between 2 input trig
The camera has two registers per line which can define a rescaler: a multiplier and a divider.
With these two registers, the end-user can change the frequency of the line.
The generated line has always a 50% duty cycle. With the combination of a multiplier and divider,
the
system can generate any frequency
The system must sample the input signal to compute its frequency.
Two parameters define the sample settings:

RescalerSize

Granularity
The Rescaler Size defines the maximum number of samples : 16bit (65536 samples).
The Granularity allows the rescaler to generate the sample periodicity. Four values are possible: 1, 4, 16 or
256 system clock cycles.
The system clock period is 20ns. So the time between samples is (Granularity x 20ns)
Trigger
Divider
Multiplier