TPS929240-Q1: EEPROM CRC Error

1. Yes, CRC checks after loading the EEPROM code to configuration register in NORMAL state

2. Certainly it always implements a EEPROM CRC check after loading the EEPROM code to configuration register in NORMAL state. 

3. The master controller can write 1 to REGDEFAULT to reset all the registers to default value and reload the EEPROM to corresponding registers in NORMAL state.
Reloading the EEPROM triggers the EEPROM CRC check. The master controller must write CLRFAULT to 1 to clear the fault flags

Hello Xiaoguang,

1. To double confirm, in case EEPROM CRC error is detected in Normal state, the registers would still be loaded with their corresponding values from EEPROM ?

2. To better clarify my colleague's inquiry; is it needed to check EEPROM CRC error with each MCU startup? Is it possible to have the TPS929240 chip reporting the error during its lifetime despite EEPROM contents not being updated since flashing at production line ?

3. To better clarify my colleague's inquiry; in case EEPROM CRC error is reported, would reloading the values through <CLRREG register> result in any different result than error being reported again? 

The only way to fix the EEPROM CRC error is to burn the EEPROM again, no reloading would fix it, right ?

Hi, Ahmed, 

1. Yes. The TPS929240-Q1 loads the EEPROM data (refer to datasheet for registers difference) every time  during INIT state or fail/safe state, then implements CRC check in normal state or fail/safe state.  

2. (a). If ACKEN is 1(default), every write command will have Status feedback, which returns FLAG_ERR status and you can know if any fault happens and what kind fault happens. 

(b). TPS929240 implements EEPROM CRC check every time when it run into normal state or fail-safe state. 

3. It depends. you may also write 1 to REGDEFAULT to reset all the registers to default value and reload the EEPROM to corresponding registers in NORMAL state. Reloading the EEPROM triggers the EEPROM CRC check. If it not works, try POR or burning the EEPROM again. 

Hello Xiaoguang,

We are asked to send read frame to register <FLAG_ERR> and check EEPROM_CRC error and if this error occurred, we should do the following more than 3 times 
    1.1- Write 1 to REGDEFAULT to reset all the registers to default value and reload the EEPROM CRC.
    1.2- Check again EEPROM_CRC.

according the previous context, we need to answer the following questions?

1- Is the pervious steps are correct to fix EEPROM_CRC error ?

2- During production phase, we don't have EEPROM_CRC error but Our concern is during life-time phase, Can EEPROM_CRC error be TRUE despite EEPROM's data not updated since production phase?

3-  Assume we have issue in EEPROM_CRC due to data corruption and we need to fix it , what is the correct behavior to fix it?
         A) Write 1 to REGDEFAULT to reset all the registers to default value and reload the EEPROM CRC?
         B) Burn EEPROM again ?