BQ27542EVM: bq

Hello Corbin,

This question has been assigned and will be answered when possible.

Thank you,
Alan

Hello, 

Please refer to the following document for our SHA authentication resources: https://www.ti.com/lit/an/sluaaq0/sluaaq0.pdf 

This document describes how to use our existing toolchain to program the SHA keys onto the gauge and to authenticate that this was done correctly. 

Regards, 

Jonny. 

In fact,  this would help me out  if it worked with a stand alone part like the bq26100.  Then I could stay compatible with the equipment that is using the SHA1 authentication, but I could change the fuel gauge in the battery to one of the newer parts.

I should explain my situation further.You may have a better solution than what I am trying to do.  Ten years ago we designed a battery that uses the b227541,. Its kind of obsolete, but still available at a high cost.  My goal would be to use a newer fuel gauge that is more readily available..  But I need to remain compatible with the equipment the battery is used in and that requires SHA1 authentication.  My thought was to add a stand alone SHA1 device like the bq26100 but I am not able to program the KEY directly into that part. So I thought maybe I could make my own using an MSP430. Hence asking for the MSP430 SHA1 code example referred to in the earlier post. Any better ideas?

Hey Corbin, 

What is the backwards compatibility that you are needing, perhaps one of our newer devices could still work here? 

Regards, 

Jonny. 

The only requirement is that is supports the SHA1 authentication as the BQ27541 did.  I can't make any changes to equipment in the field. The bq26100 would be ideal except that it does not allow me to put in my secret key.