8840A IO Card

A replacement for the GPIB interface (option 005) for the Fluke 8840A series of benchtop multimeters.

Tested With:

• Fluke 8840AF
• Fluke 8840A
• Fluke 8842A

Compiling

This project uses PlatformIO see the wiki for installation instructions.

Interfacing

You will need to connect the ESP32 with a circuit like this, by default UART2 is used:

Protocol

8840a_io_card speaks (mostly standard) SCPI on the computer side of the interface, either over 115200 baud USB serial or TCP port 5025. The identify command returns fake manufacturer/model in order to trick libsigrok to communicating without modification.

Communication with sigrok-cli and SmuView works fine.

Examples

sigrok-cli --driver scpi-dmm:conn=tcp-raw/x.x.x.x/5025 --samples 10
sigrok-cli --driver scpi-dmm:conn=/dev/ttyUSB0 --samples 10

TODO

• SCPI IP config
• Ethernet (W5500 or maybe ESP32's built in MAC/LAN8720?)

Credits

Massive thanks to Burner_357 on the EEVBlog forum