REXYGEN Community Forum

stepan.ozana

Member

Registered: 2016-10-06

Posts: 34

Rexduino 2.50.x

Hi, I'm facing a strange issue when trying to use RexDuino with RPi and REX 2.50.x (with Arduino Uno).

The simple attached example tackles servo control on DO9_PWM.

If I send a new value of duty cycle, it changes serial device from original /dev/ttyACM0   to /dev/ttyACM1.

This behaviour is confirmed by dmesg command run on RPi. If I change it via RexView on-the-fly, it stars working again, but when I set a new value again of servo position, port is changed again, to ACM0.

I have no idea why. The entire project is enclosed:

[https://www.rexcontrols.cz/forum/img/me … 8-1004.zip]

Thank you for possible support,

Stepan

tomáš čechura

Administrator

Registered: 2016-02-22

Posts: 371

Re: Rexduino 2.50.x

Hi Stepan,

it seems that there are some power supply issue regarding the description you provided - especially according to the ACM0 and ACM1 switching.

Here follows some clues in order to investigate the problem more thoroughly:

• Have a look at "dmesg" output - there should be visible if the Arduino is reconnecting.

• Try your project with plain Arduino - without any wiring to the servo motor. It works fine for me.

• Investigate "comm_status" output of Arduino subsystem if it drops from "3" to "0" and back.

• Are there any errors in REX log file?

It is possible to assign an unique symbolic name to the Arduino - see following topic on Multiple Arduino boards.

Regards, Tomas

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Raspberry Pi as a miniature industrial PC. Analog and digital I/O, RS-485 and 1-Wire bus.

stepan.ozana

Member

Registered: 2016-10-06

Posts: 34

Re: Rexduino 2.50.x

It was a power supply issue, just like you said.
Although it was supposed to work with the use of internal voltage source, an external power supply was necessary in this case.
Thanks for quick and efficient support.

tomáš čechura

Administrator

Registered: 2016-02-22

Posts: 371

Re: Rexduino 2.50.x

Hi Stepan,

glad I could help you and everything is working for you now.

Regards, Tomas

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Raspberry Pi as a miniature industrial PC. Analog and digital I/O, RS-485 and 1-Wire bus.