DRV10987: DRV10987 - EEPROM not ready

Hi 

 kindly suggest us for above query.

Hi Venkat,

  Yes, already in existing design we read EEPROM status only after MTR_DIS=1 as you suggested. Also we have given delay of 200ms after power up for reading the EEPROM ready status. For checking the Motor Driver status, we will run motor only after checking the EEPROM ready status all the time.

Thanks and regards,

R.Sivasuryan

Hi Siva,

I will reply to you by end of this week. All procedure looks fine, still I will verify if any other reason can cause this issue.

Thanks and Best Regards,

Venkatadri S

Hi Venkat,

  The following is the normal sequence after we did Power ON. we already have kept eeRefresh = 0 

DisableMotorDriver
ResetEEPROM
AccessEEPROM
WaitForReadyState
ReadEnable
ReadConfigRegisters
WaitForReadyState
EnableMotorDriver

If we changed any configuration

DisableMotorDriver
ResetEEPROM
AccessEEPROM
WaitForReadyState
ReadEnable
ReadConfigRegisters
WriteConfigRegisters
WriteEnable
WaitForReadyState
ReadEnable
ReadConfigRegisters
WaitForReadyState
EnableMotorDriver

Also let us know the EEPROM endurance cycles (1000 cycles..?) as we used to read the configuration from EEPROM every time we power ON.

Let us know whether we can do read from EEPROM every time powering ON.

Thanks and regards,

R.Sivasuryan

Hi Siva,

Reading is not a problem, you have another loop when the configuration changed you are going for writing. How many time this would have happened over the time? 

Thanks and Best Regards,

Venkatadri S

Hi Venkat,

  We usually don't change the configuration but only check the EEPROM every time powering ON to ensure integrity and proceed further things. 

The problem is with one of the device, the EEPROM is not getting ready ( eeReadyStatus = 0) and we are not proceeding further hence.

Thanks and regards,

R.Sivasuryan

Hi Siva,

Understood. Can you share the schematic? Is this device soldered on a PCB?  Can you probe V3P3 and GND and confirm if you see any noisy behavior?

How is ground planes around DRV?  Can you share me the oscilloscope observation?

Thanks and Best Regards,

Venkatadri S

Hi Venkatadri,

I privately sent my schematics for your reference and I already shared with other TU Intellectual privately during my design phase for confirmation. I have attached the V3P3 scope shot for your reference and it is clear without any noise. We have soldered in PCB and ground filled around driver IC and also provided ground plane under the driver.

FYI, While without checking the EEPROM  eeReadyStatus, we can run the motor without any issue with EEPROM data. But while reading the  eeReadyStatus it is zero and it is not getting ready. 

Kindly suggest whether we need to read EEPROM every time or we can proceed with I2C itself directly.

Thanks and regards,

R.Sivasuryan

Hey Siva,

Thanks for the update. We will aim to provide an update this week.

Best,
Akshay

Hi Siva,

If you have I2C interface always available, then you can do as you mentioned. But it is better to understand why this particular board is showing EEPROM not ready.  I will require some time to get back on this. I will keep you posted.

Thanks and Best Regards,

Venkatadri S

Hi Venkatadri,

    Kindly let me know whether we can have direct access to config registers without using the EEPROM.

Actually We have tried this bypassing EEPROM, we are directly writing config registers through I2C but while reading back the config registers the values are wrong which was not actual previously written through I2C. 

Kindly suggest us how to readback configuration registers for ensuring the configuration data written properly.

Thanks and regards,

R.Sivasuryan

Hi Siva,

Dynamic configuration is possible with EEPRM Data bypassing. Registers 0x90 to 0x96 are programable through I2C dynamically.

Please check address range you are accessing. Can you post here what you are writing and what is read? For all the register 90 to 96.

Thanks and Best Regards,

Venkatadri S

Hi Venkatadri,

 The following is register (Registers 0x90 to 0x96)  data through I2C

config_1 = 0xD02F;
config_2 = 0x1B49;
config_3 = 0x2BC5;
config_4 = 0x24B8;
config_5 = 0x3B0F;
config_6 = 0xF440;
config_7 = 0x847A;

Thanks and regards,

R.Sivasuryan

Hi Siva,

This is read data and what are you writing?

I hope I2C communication, pull up values, I2C Bit rate are all properly verified.

Thanks and Best Regards,

Venkatadri S

Hi Venkatadri,

   Sorry, this is the data we are writing and while reading the same register values it is completely different. And I have already shared schematics privately to you for reference and verified the pull up resistor values for proper communication.

Thanks and regards,

R.Sivasuryan

Hi Siva,

Do you have USB2ANY interface with you? Can you try communicating to this device with USB2ANY with GUI and confirm the behavior?

Including eeprom busy status also.

Thanks and Best Regards,

Venkatadri S

Hi Siva,

Any progress on this?

Thanks and Best Regards,

Venkatadri S