Dalsa PC2-CamLink, User Manual

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PC2-CamLink User's Manual Part I: PC2-CamLink Board
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other words, +5V is connected to E and the sink trigger source is connected to Ext_Trig-.
This will normally require the application the invert the polarity of the trigger in the camera
configuration file.
Many TTL devices will not supply enough current to reliably drive the E of an opto-coupled
input; a buffer is needed between the TTL output and the E input. One possibility is a CMOS
buffer with TTL compatible inputs, such as the 74AC240 (inverting buffer) or 74AC241 (non-
inverting buffer). These devices can supply up to 24mA at close to the supply voltage. The other
alternative is to connect your TTL device to Ext_Trig- and connect a +5V pull-up to E as
mentioned above.
Pinout :
Positive side (anode) Negative side (cathode)
Opto trigger 1 DB-15, pin 1 DB-15, pin 9
Opto trigger 2
DB-15, pin 2 DB-15, pin 10
LVDS
LVDS (Low Voltage Differential Signaling) uses low-voltage dual-wire systems running 180° apart.
This enables noise to travel at the same level, which in turn can get filtered out more easily and
effectively.
Two LVDS trigger inputs are available on PC2-CamLink (for a total of 4 pins). These inputs are
typically implemented using the National Semiconductor DS90LV028A LVDS line receiver or a
compatible device.
Pinout:
Positive line Negative line
LVDS trigger 1 DB-15, pin 4 DB-15, pin 11
LVDS trigger 2 DB-15, pin 5 DB-15, pin 12
SW Trigger
A software trigger is available to programmatically control the trigger event. This is generated by a
function call from the application.
User Timer
The PC2-CamLink offers a user timer that can be used to fire a frame acquisition at a specified frame
rate. Note that the user timer is asynchronous to all input pins.
The user timer has a minimum frequency of 0.1Hz and a maximum frequency of 10kHz with a step
size of 0.1Hz.