BQ27427EVM: learning cycle

Hello Jure,

1. First use GPCCHEM tool to get the correct ChemID that matches your battery, then set chemID and run learning cycle. This is the necessary.

2. This document can provide a lot of information www.ti.com/.../sluaa98

3. Update status parameter indicates if the gauge is ready to provide gauging results

Hello Shirish,

thanks for your answer.

1. Ok

2. Since we do not work in Windows environment and consequentially can not use BQSTUDIO, the document does not help in my case. Nonetheless, we want to learn how to control the BQ27427 from the host microcontroller on our device.

3. Thanks for pointing me to the "Update status" register. If I understand correctly, there are two relevant bits (ignoring bit 7 for now):
- "00" is the default state and means normal operation
- "11" means that the learning cycle is in progress?

Does this mean that after POR, and configuration of ChemID + parameters (e.g. Design capacity, Design Energy, etc.) one has to:
- set the bits in Update Status register to "11"
- perform the learning cycle
- clear the bits in Update Status register to "00"

I am looking at the "Achieving The Successful Learning Cycle" (https://www.ti.com/lit/ml/slua903/slua903.pdf) document, but the commands in the procedure description do not match commands/registers in BQ27427 (e.g. There is no (Gauge) enable command (0x21)).

2. The host controller writes a "golden image" on startup because the bq27427 power off will result in RAM being reset

3. The entire golden image is read after a successful learning cycle and then this golden image is used at every powerup

Refer this document https://www.ti.com/lit/ug/sluubn3/sluubn3.pdf

Yes, there are differences for system side gauges. Set Update status bits to enable learning. See TRM section 7.4.2.3.2 Update Status

I understand the fact about data loss on power-down and the need to write parameters (golden image) from the host on power-up.
I am also aware about the BQ27427 TRM section 7.4.2.3.2 Update Status, however from that description it is still not clear to me how does one begin/end the learning cycle process. In my previous reply, I wrote my guess/interpretation of the procedure with my own words - is that procedure correct?

The SLUUBN3 (xx426) guide does not describe the steps on how to actually perform the "learning cycle".

So, to summarize my question again:

Does a programmer need to set the Update Status bits to "11" in order to begin the learning cycle? And reset to "00" when the learning cycle is finished?
(ignoring bit 7 in this example)

Okay, thank you!