Trigger

From ElphelWiki
Jump to: navigation, search

Description

10369 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 phone cable with RJ14 is used. To program trigger go to: http://192.168.0.9/parsedit.php -> 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

Parameters

parameter description
TRIG Trigger mode enable. Currently 0 - free running, 4 - triggered by external signal or internal FPGA timing generator.
TRIG_PERIOD FPGA trigger sequencer output sync period (32 bits, in pixel clocks). 0- stop. 1 - single, >=256 repetitive with specified period (values 2..255 are reserved for programming timestamp communication)
TRIG_DELAY FPGA trigger sequencer trigger delay, 32 bits in pixel clocks
EARLY_TIMESTAMP When 0 - frame sync (start of the frame readout) will be used for timestamping of the images, when 1 and the trigger mode is external (physically external to the camera or just when sensor runs from the FPGA timing generator) the start of exposure will be used for time stamping (exposure time earlier). This is the default mode to prevent recorded frame period jitter caused by automatic exposure adjustments
TRIG_CONDITION FPGA trigger sequencer trigger condition, 0 - internal, else dibits ((use<<1) | level) for each GPIO[11:0] pin). Example:0x200000 - input from external connector (J15 - http://wiki.elphel.com/index.php?title=10369#J15_-_SYNC_.28external.29 ), 0x20000 - input from internal (J13/J14 - http://wiki.elphel.com/index.php?title=10369#J13_-_SYNC_.28internal.2C_slave.29 )
TRIG_OUT level_when_active). Bit 24 - test mode, when GPIO[11:10] are controlled by other internal signals. Example: 0x800000 - output to external (J15 - http://wiki.elphel.com/index.php?title=10369#J15_-_SYNC_.28external.29 ) connector, 0x80000 - to internal (J12 - http://wiki.elphel.com/index.php?title=10369#J12_-_SYNC_.28internal.2C_master.29 )

Single frame triggering from PC

Enable

http://192.168.0.9:8081/trig/pointers
  • 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:

http://192.168.0.9/parsedit.php?TRIG&TRIG_CONDITION&TRIG_DELAY&TRIG_OUT&TRIG_PERIOD&TRIG_BITLENGTH&EXTERN_TIMESTAMP&XMIT_TIMESTAMP&IRQ_SMART&refresh

Trigger/Refresh

http://192.168.0.9:8081/trig/pointers

Status

http://192.168.0.9/parsedit.php?immediate&TRIG&TRIG_PERIOD&IRQ_SMART&SENS_AVAIL&FRAME

Disable

  • Update the TRIG_PERIOD in the PHP interface - or simply check the box and hit Apply:
http://192.168.0.9/parsedit.php?TRIG&TRIG_CONDITION&TRIG_DELAY&TRIG_OUT&TRIG_PERIOD&TRIG_BITLENGTH&EXTERN_TIMESTAMP&XMIT_TIMESTAMP&IRQ_SMART&refresh
  • Refresh until the changes are applied (with Program Ahead = 3 it's 3 times):
http://192.168.0.9:8081/trig/pointers

Examples

Before setting trigger options it's better not to launch the Camera Control Interface after booting. Go straight to Parameter Editor.

Internal (from fpga generator)

  • COMPRESSOR_RUN=0x0
  • TRIG_CONDITION=0x0
  • set the TRIG_PERIOD
  • TRIG=0x4
  • COMPRESSOR_RUN=0x2

OR

Internal (from fpga generator) + output the trigger signal

  • COMPRESSOR_RUN=0x0
  • TRIG_CONDITION=0x0
  • set the TRIG_PERIOD
  • TRIG=0x4
  • TRIG_OUT=0x800000
  • COMPRESSOR_RUN=0x2

External (J15)

Receive: GPIO[10] needs to be configured to receive the trigger signal:

  • Step 0: Link to parameters that will be changed:
http://192.168.0.9/parsedit.php?TRIG&TRIG_CONDITION&TRIG_OUT&TRIG_PERIOD&COMPRESSOR_RUN
  • Step 1: stop the compressor
COMPRESSOR_RUN=0x0
  • Step 2: (Same parameters for master and slave)
TRIG_OUT=0x800000
set the TRIG_PERIOD=0x5B8D800 (=96000000 dec, =1sec =1fps)
TRIG_CONDITION=0x200000
TRIG=0x4
  • Step 3: restart the compressor
COMPRESSOR_RUN=0x2

Generate: GPIO[11] needs to be programmed - set TRIG_OUT=0x800000


Notes:

TRIG_CONDITION: a 22-bit register where 2 bits are used for programming each GPIO (from 0 to 11, e.g., TRIG_CONDITION[1:0] will program GPIO[0]) - MSB enables input and LSB selects active  trigger signal level.

TRIG_OUT: Same as in TRIG_CONDITION register - MSB enables and LSB selects level.

OR

GPIO[11] & GPIO[10] can be set by following http://192.168.0.9/sync.php?role=detect&channel=external

External (J12-J14)

Master

  • TRIG_OUT=0x80000 (J12)
  • set the TRIG_PERIOD=0x5B8D800 (=96000000 dec, =1sec =1fps)
  • TRIG_CONDITION=0x20000
  • TRIG=0x4

Slave

  • TRIG_OUT=0x80000
  • set the TRIG_PERIOD=0x5B8D800 (=96000000 dec, =1sec =1fps)
  • TRIG_CONDITION=0x20000 (J14)
  • TRIG=0x4

Links

10369 Circuit Diagram, Parts List, PCB layout