BQ27542-G1: BQ27542-G1 doesn't exist from rom mode but i2c write didnot show any failure

  Please check and follow the sequence from bq27542-G1 TRM (Technical Reference Manual) page 111 figure B-5. "ROM Mode Exit Sequence in I2C or HDQ".

 Thanks!

Phil

I am doing the exact same thing. But still device cannot come out of ROM mode.

Question: Should i write the full bqfs file before exiting ROM mode?? Now i had performed only two  write operation.

  Yes. Here are some highlights: Once in ROM mode, the user test setup must be able to open the BQFS or DFFS file and perform each of the I2C or HDQ transactions in strictly the same order as given with the FlashStream file. Once completing all commands within the FlashStream file, the user test system sends the Exit ROM mode procedure (Figure B-5). At least a 250-ms delay must occur before attempting to proceed with I2C or HDQ communication to the target device using the I2C address 0xAA after exiting ROM Mode.

Phil

Hi Phil,

I wrote some C code to perform i2c transactions. Now i m parsing whole bqfs file. Now another problem arises is i m getting check sum error.
W: 16 00 04 00 00 00 83 DE
W: 16 64 65 01
X: 200
C: 16 66 00
W: 16 00 02 00 00 00 EA FF 33 A0 FA 33 12 FB 33 8C FE 33 D1 FE 33 FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F FF FF 3F 01 02 3F 58 CB 33 FB 00 08 01 00 00 00 00 00 FF AA 0E FB A7 0E FF A6 0E FF A1 0E FF A0 0E FE A3 0E 62 A2 0E D2 FF 3A FF A1 0E 63 A0 0E FF A3 0E
These instructions are going well. From the next write (ie from W: 16 64 D5 35), i m getting i2c failure . Further write gives i2c failure.
Further, In compare instruction, the read data is 0x02, instead of 0x00. I believe it is a checksum error.

Similar issues has been reported before.
e2e.ti.com/.../221507
e2e.ti.com/.../158561

Any suggestions please??

i2c write failure issue has been cleared. It was because i2c buffer size was 32 bytes. So when we write 96 bytes, buffer is overflowed and thus throwing off the whole program.

But checksum error issue is still there. When i read the register (in compare instruction), it doesn't match with the value in bqfs file. Hope it is a checksum error. It happens for all compare instruction. Read data was 0x30, 0xff, 0x34 etc..

Any updates??

i bought a new custom board and tried loading dffs file into it. Upto this command, W: 16 00 03 00 00 i2c write and checksum read was successfull. On the next command , W: 16 64 03 00 we got i2c failure (error : unspecified reason). So the custom code will perform Exit rom mode procedure.
When we checked the address of the device, it was showing 0x0B. So we run a code that perform exit from ROM mode. Again we checked device address, and it gives 0x55.
Again we tried loading the same code. First few times , it behaves as mentioned above
Then it respond only to 0x0B address.
What should we do next??
Does this means that fuel gauge is bricked? if so, will it respond to any slave address?
what procedure should we follow, so as to do this, without bricking fuel gauge?

Thanks in advance

I need more time to study your case and will give answer as soon as I get it.
Thanks!
Phil

Hi Pavitra,

How did you extract the flashstream file. Did you use bqstudio to do the extraction.

Are you able to program the flash back on the device using bqstudio?

What firmware  version of EV2300 or EV2400 are you using? you might need to update the firmware version.

thanks

Onyx

Flashstream file was provided by client. They used bqstudio.

I dont have EV2300 and EV2400. Will try to get one and try above mentioned procedures.

Is there any other method to verify ?

Hi Onyx Ahiakwo,

I recovered bq27542 using EVM2400 and bqstudio . Now i am getting everything as expected.

bq27542 firmware update usinf bqfs and dffs are successfully completed.

Thanks