PyRelayCtl is a library to control FTDI FT245R based relay boards. This includes the SainSmart 4-channel 5V USB relay board. The outlets can be switched on and off via USB.
The library depends on PyUSB (https://github.com/walac/pyusb).
On Debian PyUSB can be installed using:
apt-get install python3-usbrelctl.py is a command line tool to control attached relay boards.
printenv.py shows how to use the library to switch on a computer, read the U-Boot environment variables and then switch it off again.
Per default, only root is allowed to use devices directly, therefore the library also only works as root.
To allow group relayctl access create file /lib/udev/rules.d/60-relayctl.rules with the following content:
SUBSYSTEM=="usb", ATTR{idVendor}=="0403", ATTR{idProduct}=="6001", GROUP="relayctl", MODE="660", ENV{MODALIAS}="ignore"Then reload the udev rules with:
udevadm control --reload-rulesCopyright (c) 2016, Heinrich Schuchardt <xypron.glpk@gmx.de> All rights reserved.
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