I have a question concerning the Update Status register reading 04 in the bq20z45R1 chip.
We have received some units from the field for firmware updates and noticed that the Update Status register is reading 04.
When we first build and program these units the update status is set at 02.
We then perform a board test and turn impedance tracking on, run the test then reset the update status back to 02.
Then we install the cells, turn on the impedance tracking and run the unit through a final test before shipping.
At no time during this process is the update status ever set to 00.
When these units are used in the field there is no access to the fuel gauge.
When we received these units back for updates we noticed that the update status is set to 04 on all of the returns we have checked so far (about 20).
Do you know why we might see 04 after we set it to 06 from the original state of 02?
Does the bq20z45 change this value during normal operation?
On these rework units we are currently changing the value of the update status register to 06 before we ship them out.
Do you see any issue with this, or is it necessary to make any change?