TLF35584 SPI write to Protected registers - Not responding

[Vipula]

Hi, 

I am using TLF35584 with STM32-nucleo-F103RB. Upto now I can read and write the registers and clear flag registers. Now I am trying to SPI write to Protected registers. I have followed following sequence but when I am reading the register PROTSTAT, I send 0x5000 and received 0x8002. Window watchdog and error pin doesnt disable yet(DEVSTAT). I have attached the screenshots for your reference.

Unlock:
0x8756
0x87DE
0x86AD
0x8625

Disable watchdog and error pin:
0x8D27
0x8A01

Lock:
0x87BE
0x8668
0x877D
0x8795

Can anyone guide me on this? I need to change the state init to normal after disabling watchdog and error pin.

Thank you.

[Anshika_G]

Hello,

When I tried to decode the Hex value as given by you, it matches with the datasheet values, means unlock bit and lock bit sequence is fine. 

For transitioning from INIT -> NORMAL-state:
Prerequisites:
• Watchdog(s) need to be serviced once according to default configuration or according to reconfiguration within the INIT timer
• ERR monitor needs to be serviced with a valid signal (minimum 3 periods) or disabled within the INIT timer.
• If functional watchdog is activated, a valid FWD triggering needs to be provided.
• A delay of 60µs after the provided services has to be considered to ensure proper release of internal validation signals.

Triggering Events:
• State transition is only initiated by the SPI command “Go to NORMAL”.

Please make sure that you are sending the valid SPI command.

Best Regards,
Anshika

[liwen]

Have you solved this problem? I also sent the same sequence data with you. My dog and err were not successfully disabled, and the received data were not correct. I felt that the value of the register was not written at all. I don't know what's wrong😭

[xiaoxuan]

您好，

请问你解决这个问题了吗？

我遇到了同样的问题，看门狗和ERR监控禁止不了😭

[AnilKumar · Accepted solution]

Hello,

Please find the attached right sequence and expected return value in status registers for a successful write to protected registers.

Also note the access to the protected registers is possible in INIT, NORMAL and WAKE state.

Please also check the IF register to debug the cause for failure.

Thanks

Anil