Trigger 393

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Revision as of 13:41, 12 October 2018 by Oleg (talk | contribs) (internal connectors)
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10389 board is required.

The triggering is used for one or several cameras synchronization or setting the frame rate (or fps). The conditions of the trigger can be generated either internally or externally. For external triggering a 4-conductor 2.5mm audio plug with cable (example: digikey) is required.

To program trigger go to: => External Trigger Controls

NOTE: Be careful with changing parameters when TRIG=4. Camera drivers are driven by the frame sync interrupts from the sensor, so if the sensor is not triggered - everything can get stuck. The Program Ahead value sets the number of frame sync interrupts the camera will wait wait for until a parameter is reprogrammed.

External Trigger Controls page


parameter description
TRIG Trigger mode. 0x0 - free running, 0x4 - triggered by external signal or FPGA timing generator, 0x14 - triggered in GRR mode
TRIG_MASTER Master sensor_port (0..3) for triggering setup, other ports will have settings duplicated
TRIG_CONDITION FPGA trigger sequencer trigger condition, 0 - internal, else dibits: 00 - do not use, 01 - keep, 10 - active low, 11 - active high for each GPIO[9:0] pin). 10389 board inverts signals, so 0x80000 - input from external connector, 0x08000 - input from internal flex cable (as in Eyesis)
TRIG_DELAY FPGA trigger sequencer trigger delay, 32 bits in pixel clocks (100MHz or 10ns)
TRIG_OUT FPGA trigger sequencer trigger output to GPIO, dibits: 00 - do not use, 01 - keep, 10 - active low GPIO output, 11 - active high GPIO output. 10389 board inverts signals, so 0x02000 - output to external connector (active high), 0x20000 - output to internal flex connector
TRIG_PERIOD FPGA trigger sequencer output sync period (32 bits, in pixel clocks (100MHz or 10ns)). 0- stop. 1 - single, >=256 repetitive with specified period
TRIG_BITLENGTH Bit length minus 1 (in pixel clock cycles) when transmitting/receiving timestamps, without timestamps the output pulse width is 8*(TRIG_BITLENGTH+1). Legal values 2..255
EXTERN_TIMESTAMP When 1 camera will use external timestamp (received over inter-camera synchronization cable) if it is available (no action when external syncronization is not connected), when 0 - local timestamp will be used
XMIT_TIMESTAMP Specify output signal sent through internal/external connector (defined by TRIG_OUT). 0 - transmit just sync pulse (8*(TRIG_BITLENGTH+1) pixel clock periods long), 1 - pulse+timestamp 64*(TRIG_BITLENGTH+1) pixel clock periods long


Internal periodic trigger (10 fps, from fpga generator)

Internal periodic trigger (4 fps, from fpga generator) + output the signal to external port

External trigger receive

Recover from missing external trigger signal to internal trigger

Manual triggering from PC

  • TRIG=4 should be set in advance
  • The command automatically sets a single-shot trigger mode with TRIG_PERIOD=0x1, but it writes the register directly into the FPGA,

not updating the TRIG_PERIOD in the PHP interface:


Check status


Update the TRIG_PERIOD in the current frame
Update the TRIG_PERIOD from the user interface


  • 10389 extension board
  • 103891 adapter board for external trigger connection

10389 trigger testing

external connector

In this test the camera triggers itself via audio cable. For cable wiring see 103891.

  • To test:
visual: LED is blinking
software: frame counter is running
  • It's easy to modify the cable to trigger itself and other multiple cameras.
10389 extsync selftest.jpeg

internal connectors

In this test the camera triggers itself via 4-pin flex cable.

  • Connect as displayed on the pictures below.
    • J4 - trigger output (master port)
    • J5-J6 - trigger input (slave ports)
  • To test:
- connect a sensor to port 0
software: frame counter is running
10389 intsync selftest.jpeg
10389 intsync selftest closeup.jpeg