How To Access the STROBE Output
The MA13X cameras can output a STROBE signal when taking a Still Image. This can be used to trigger an LED flash in sync with the exposure.
Steps
1
Alternatively if you have the skills in house to solder a 0402 resistor and remove another 0402 resistor then you can modify an existing board. R47 on the top side of the board, above the fiducial mark next to the pushbutton is not populated – you need to add an 0402 resistor here. It can be 0 ohms or a small value less than 22 ohms.
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2
Also remove R48 off of the bottom side of the board, it’s very close to the strobe pin on the connector and you can follow the track on the bottom of the board, from the connector, to find it.
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3
This will route the strobe signal to the 4 pin white connector P2. It will route to the pin closest to the middle of the board. The pin next to it is 0V. The pin closest to the edge of the PCB is 3.3V.
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4
Set the flash mode by writing to the camera register FLASH_MODE. This can be achieved using OneView Tools>Cam Register Access. The FLASH_MODE supplementary register has address [0x0D] [0x0A]. There are four modes: 0 LED 1 XENON 2 Pulsed LED 3 LED Auto (LED- Pulsed LED automatic switching) In modes 1 thru 3 the Shutter Time and Gain are fixed and set by writing to the camera registers FLASH_FORCE_SHUTTER [0x0D][0x0D] and FLASH_FORCE_ISO[0x0D] [0x0E]. In mode 0 the flash time is longer than the actual exposure time but the exposure will match the streaming video exposure meaning you should have an idea of how the still will look by viewing the video before taking the image. In the other modes the exposure is not necessarily the same - it depends on what settings you have for the video and the values of FLASH_FORCE_SHUTTER/FLASH_FORCE_ISO.
5
Set FLASH_FORCE_SHUTTER [0x0D][0x0D]. Again use Tools>Cam Register Access. The range of valid values is 0x1b to 0xxx meaning the exposure time can range from
6
Set FLASH_FORCE_ISO [0x0D][0x0E] The range of valid values is 1 to 65555 set by writing two bytes.
7
Then we must enable the STROBE output from the camera module by writing to 0x01 to camera register FLASH_SW[0x0D][0x0B]. Writing 0x00 will disable the STROBE output.
8
The UNITY board needs to be configured to route the STROBE signal to the white, 4 pin connector on the PCB. The default configuration uses the same connector for debug purposes. Please order the correct configuration of the UNITY board; Part Number: 01999010601 Unity PCB with FCC, STROBE Out.
9
Finally you need to take a still image by pressing <ENTER> on the keyboard or navigating to Stills>Get Still and you should see a 1.8 volt strobe signal on the connector pin. This signal should only be used to trigger a flash device and not supply the power. These steps can all be incorporated into software using the OneView SDK.