An ESP32 dongle for Owon B series multimeters and a TestController definition file
The Owon B series multimeters use BLE GATT to transmit messages. The reading is transmitted as a signed magnitude binary number. There is an excellent discussion of the protocol at https://github.com/DeanCording/owonb35.
These multimeters also require a CC2450 based BLE dongle to communicate with a PC.
Together these factors make it very difficult to use these multimeters on a PC.
This project includes code for an ESP32 based dongle that should work with any ESP32 model that has a USB port. It has been tested with an ESP32-WROVER DevkitC.
The .txt file is an instrument definition file for TestController. https://lygte-info.dk/project/TestControllerScriptingExample%20UK.html
JT Cash has improved this code (July 2023) - see https://github.com/jtcash/OwonB41T/