Legal Removal Request

Post: I have just tested the Expander Pi C++ library with the demo-adcread.cpp program on a Raspberry Pi 4 and 3+ using the latest version of Raspbian Linux and it appears to be working correctly with voltages showing up on each channel. Do you have a spare SD card you could use to create a clean installation of Raspbian Linux? Enable I2C and SPI on the clean image using our [url=/kb/article/1/i2c-part-2-enabling-i2c-on-the-raspberry-pi]I2C tutorial[/url] and [url=https://www.abelectronics.co.uk/kb/article/2/spi-and-raspbian-linux-on-a-raspberry-pi]SPI tutorial[/url] and download the Expander Pi C++ library from GitHub. Try compiling the demo-adcread program using g++ with the command: [pre][code]g++ demo-adcread.cpp ABE_ExpanderPi.cpp -Wall -Wextra -Wpedantic -Woverflow -o demo-adcread[/code][/pre] If the demo-adcread program works on the clean Raspbian image then that will narrow the problem down to a configuration issue on your Raspberry Pi installation. In your QT program are you reading all the ADC channels from a single thread or are they being processed on separate threads? If you are using separate threads that could cause a problem if more than one thread tries to read from the ADC at the same time. Also, do you have any other programs running on the Raspberry Pi that are trying to access the SPI bus?