am5728: RSTOUTn asserts periodically

Ronald Edgar

Part Number: AM5728
Other Parts Discussed in Thread: AM5728

I have a custom design incorporating the bulk of the EVM design for an AM5728. After power up, RSTOUTN asserts periodically approximately evert two seconds. I do not have any way for the processor to boot successfully but I have given SYSBOOT several different legitimate values but none help. Is this expected behavior? What can I do about it to prevent warm restart to the PMIC (other than disconnect the RSTOUTN line which I have done in order to make progress in other directions. Any suggestions are gratefully received.

Many thanks, Ron.

over 8 years ago

0 Biser Gatchev-XID over 8 years ago

TI__Guru**** 393215 points

Are you trying to boot some software? Please provide more details.

0 Ronald Edgar over 8 years ago in reply to Biser Gatchev-XID

Intellectual 820 points

No, I don't have my code quite ready yet. I am trying to run boundary scan but get reset every two seconds by the RSTOUTN signal from AM5728 to PMIC. Is this normal behavior, who is issuing the reset, and how can I stop it?

0 Biser Gatchev-XID over 8 years ago in reply to Ronald Edgar

TI__Guru**** 393215 points

Yes, this is normal. It's the device internal watchdog timer.

0 Ronald Edgar over 8 years ago in reply to Biser Gatchev-XID

Intellectual 820 points

Is there any way of stopping this short of boot code? On by default is counter-intuitive.

0 Ahmad_Rashed over 8 years ago in reply to Ronald Edgar

TI__Genius 13567 points

Hi Ronald,

What is the sysboot value you are using? Can you set the boot device to something outside of the "production booting" part of the table?

0 Ronald Edgar over 8 years ago in reply to Ahmad_Rashed

Intellectual 820 points

I have tried several. I have easy control over bits 0:5 and, with a little more effort, all of the others. What value do you suggest? Many thanks, Ron.

0 Ronald Edgar over 8 years ago in reply to Ronald Edgar

Intellectual 820 points

My default value is (0:15) 1001 1100 1000 0001

0 Ahmad_Rashed over 8 years ago in reply to Ronald Edgar

TI__Genius 13567 points

Hi Ronald,

You gave me sysboot[5:4] = 0b11 and sysboot[3:0] = 0b1001. It looks like that would be NAND from "production booting". Are you able to try sysboot[5:4] = 0b10 and sysboot[3:0] = 0b0001 instead? That would be [0:15] 1000 0100 1000 0001. The setting will still be NAND but it isn't considered "production booting". A note in the TRM says in production booting "After 10 failed loops through the device list, ROM code initiates immediate global warm reset".

If that doesn't work here is a second thing to try: go back to your first setting except with sysboot[5:4] = 0b01 (that would be [0:15] 1001 1000 1000 0001). It will attempt SD, fail to find an image, and then halt/wait instead of reboot.

Regards,
Ahmad

0 Ronald Edgar over 8 years ago in reply to Ahmad_Rashed

Intellectual 820 points

I will try the settings you suggest and let you know the result. Many thanks, Ron.

0 Ronald Edgar over 8 years ago in reply to Ronald Edgar

Intellectual 820 points

That works, many thanks! Ron.

Processors

Processors forum

am5728: RSTOUTn asserts periodically