ADLINK PCI-9820 - Manual (Page 40)

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• Operation Theory
T
w
SSI_TRIG2
T
w
= 20 ns minimum
Figure 4.15 SSI_TRIG2 input signal timing
As an output, the SSI_START_OP signal reflects the operation start signal in
a pre-trigger or middle-trigger acquisition sequence. Please refer to Fig 4.2 -
Fig 4.5 for the relationship between the operation start signal and the acqui-
sition sequence.
As an input, the PCI-9820 accepts the SSI_START_OP signal to be the op-
eration start signal in a pre-trigger or middle-trigger acquisition sequence.
The signal is configured in the rising edge-detection mode. Fig 4.16 and Fig
4.17 show the SSI_START_OP signal input and output timing requirements.
For enabling output operations, users can use the function SSI_SourceConn()
to output the SSI_TRIG2 and SSI_START_OP signals.
For the input operations, users can select TRSRC_SSI_2 to set SSI_TRIG2
and SSI_START_OP as the source of the trigger event and operation start
signal.
T
w
SSI_START_OP
T
w
= 2 TIMEBASE clocks
Figure 4.16 SSI_START_OP output signal timing
T
w
SSI_START_OP
T
w
= 20 ns minimum
Figure 4.17 SSI_START_OP input signal timnig
4.7.4 Comparing the different trigger sources from SSI
When selecting TRSRC_SSI_1 as the trigger source input, the signal
SSI_TRIG1 reflects the trigger event signal in an acquisition sequence.
However, when synchronizing multiple PCI-9820 devices, each PCI-9820