Other Parts Discussed in Thread: BQ30Z55, BQEVSW
Hi,
I have an bq30z55 that I need to unseal and program it. Because I don't have any EV2300 or 2400 I'm trying to do this from a Raspberry PI 3 B+ with it's I2C bus and a C code wrote by myself from the SHA1 example I found on the site for MSP430. Also there is no need for an investment in an EV2300 since this will de done one time only. So after I'm setting up the I2C bus and address I'm sending 0x31 to 0x00 and I'm reading the random challenge send by the device from 0x2F. I'm computing the HMAC 2 times as specified in SLUA359 and SLU389a (of course keeping in mind about the LSB in the random message sent by BQ). Also the function was tested against the example given in SLUA389a and the output of the SHA-1 matches the result in the document. Yet, when I'm trying to unseal the device, it isn't working. I will attach the binary logic dump from the logic analyzer. They can be imported in sigrok for the whole i2c session. The key is the default 0x0123456789abcdeffedcba9876543210. Can anyone tell me what is wrong?
Thanks,
Ciprian
