Using GUI to communicate with MPF42791


I’m looking into validating Fuel Gauge MPF42791 for my BMS application.

Based on reference design’s User Guide, accessible from here:

the document on §5.2 mentions about a possibility to convert GUI’s UART messages into I2C messages for the Fuel Gauge but fails to be more clear on how to do that - like what messages the GUI sends out and expects back when trying to connect to MPF42791 via GUI ?

I was able to record a serial API message upon connect (only to FG) but I am failing to understand the content of the length, data frame and resulting CRC bytes - since they don’t add up and have no correlation to the FG’s registries.

I was wondering if you could support connecting to a single MPF42791 fuel gauge chip with my own MCU without the needed the full reference design (costing around 1k€).

Yes, you can connect the fuelgauge to your own MCU, and communicate. It can work with other Analog Front Ends (AFEs) protection devices as well.

Full reference solution/design is to get familiar with the full range of capabilities of our fuel gauge.


Perhaps I should’ve phrased the final question:

“How can I make the BMS GUI application speak to my own MCU that is then connected to the Fuel Gauge?”

But I have now received support to achieve this. At least configuring the FG via GUI works. Monitoring currently won’t work, as I expect, this is more suited for the eval board and not for customer’s own setup… (?)

Although I see that the GUI in Monitoring mode, simply asks all of the MPF42791 registries. If all parameters are filled, the monitoring might work…