Redundancy of nPORRST pin

Sh.Sasaki

Guru 13625 points

Other Parts Discussed in Thread: TMS570LS1224

Hi,

I have question about redundancy of nPORRST pin.

Now, I use the TMS570LS1224 and TPS65381.

These devices are connected by SPI pin and Reset(nPORRST & NRES) pin.

Please teach me the following.

When using this combination:

If the SPI terminal is damaged, reset signal is output to nPORRST(TMS570) from NRES(TPS65381) by QA watch dog.
This means that system can detect the error of the SPI terminals.

If the NRES terminal is damaged, TPS can't output reset signal.
This means that TMS570 can't detect the error of NRES terminals.

Is there a way TMS570 detects the error of NRES terminals.

Best regards,

FSSer

over 10 years ago

0 Zhaohong Zhang over 10 years ago

TI__Mastermind 22715 points

If NRES terminal is bad, the MCU will not boot.

Thanks and regards,

Zhaohong

0 KGreb over 10 years ago

TI__Mastermind 23000 points

One point which may help is that the nRST signal of the MCU is bidirectional. If nPORRST is asserted, you can monitor the state of the nRST and confirm that the reset has propagated internally. This can help external logic determine if there is a problem with the MCU when an external reset is requested (such as a pin fault on nPORRST).

In your example you are looking at a multiple point fault - is the combined probability calculated large enough that you perceive this a likely event?

Regards,
Karl

0 Sh.Sasaki over 10 years ago in reply to KGreb

Guru 13625 points

Thank you for reply.

I got a hint from yous advice.

Best regards,

FSSer

Arm-based microcontrollers

Arm-based microcontrollers forum

Redundancy of nPORRST pin