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Hardware serial gives no module output without USB connection

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I have a microcontroller connected to the serial output of the JeVois camera. Via this serial line I can send commands to the camera and receive its response.

For the DemoArUco module, when I power up the camera, I receive the boot messages:

INFO: JeVois 1.9.0

INFO: Linux version 3.4.39

INFO: CPU: 1344MHz, 30C, load: 0.24 0.05 0.02 1/57 87

INFO: MemTotal: 238428 kB, MemFree: 170328 kB

INFO: OUT: YUYV 640x300 @ 60fps CAM: YUYV 320x240 @ 60fps MOD: JeVois:DemoSaliency C++


Then I issue a number of commands:

setpar serout None


setmapping2 YUYV 320 240 30.0 JeVois DemoArUco

setpar serialdev Hard

setpar serlog Hard

setpar serstyle Detail

setpar serout Hard


And get the response:


ERR Unsupported command [streamoff]

INF Engine::setFormatInternal: OUT: NONE 0x0 @ 0fps CAM: YUYV 320x240 @ 30fps MOD: JeVois:DemoArUco C++

INF Camera::setFormat: Camera set video format to 320x240 YUYV

INF Engine::setFormatInternal: Instantiating dynamic loader for /jevois/modules/JeVois/DemoArUco/DemoArUco.so


INF Engine::setFormatInternal: Module [DemoArUco] loaded, initialized, and ready.

ERR engine:serialdev: Provided value [Hard] rejected because Parameter is frozen




INF Camera::streamOn: 5 buffers of 153600 bytes allocated

INF Gadget::streamOn: 4 buffers of 384000 bytes allocated


INF ArUco::detectMarkers: Loaded camera calibration from /jevois/share/camera/calibration320x240.yaml

And after that I receive the correct output if an ArUco code is in view, e.g.:

D2 U17 4 -284 215 -384 205 -382 178 -281 188

This all works fine as long as i power the camera via the USB of my computer (no jevois software such as jevois-inventor is running on this computer). However, when I power the camera via a power-only USB plug (so no data connection to the computer) I get the same response to the commands, but I receive no output if an ArUco code is in view.

What do I need to do to get this working without a connection to my computer?

It seems related to the problem mentioned here, but it gives no solution.

asked Nov 28, 2018 in User questions by Jeroen (120 points)

1 Answer

0 votes
for reference, this was fied online by following this tutorial:


and putting the commands in initscript.cfg
answered Nov 29, 2018 by JeVois (46,580 points)