This board perfectly fit my need. It took a while to get it working from my Python code, but when Peter pointed out the C reference code I got my code working properly very quickly. And he's improved the boards, adding Qwiic connectors so I can't even plug in the control lines wrong! Thanks, Peter!
March 15, 2021
good priced prosux, bwtter current handling than others
Worked perfectly. Great documentation with clear instructions. I'm using the first one with a RaspberryPi and controlling it remotely using python and it worked without any issues. I had a coulpe of questions about also getting it working with Domoticz (home automation software) and Peter pointed me in the right direction to get a basic plugin working so I've now ordered a second one to use for that project.
Jan. 4, 2021
8-channel relay board for Raspberry Pi and Arduino
This is a great product. I bought the I2C version. It worked right from the start. (Rapsberry PI 4 - 4GB). Comes with a great documentation and instructions usable also for Raspberry newbies like myself. The seller even answered my electronic related question within short notice. Great service!
Feb. 24, 2020
USB GPIO interface - excellent product at a modest price!
This is a professional quality product, with a free software download of the same standard. The comprehensive documentation makes it easy to interface both hardware and software. It is well worth the modest price, which includes shipping in the UK. I am using this device to control the intelligent charging of my Toshiba laptop battery in order to prolong battery life. Running Linux, I compiled the supplied 'controlio' source code without any problems to get the required 64 bit binary. A bash script runs as a cron job at five minute intervals, checking the charge level and switching the charging current on and off as required, via a relay controlled by three paralleled outputs of the GPIO interface. Many thanks for a great product, Peter.