Regarding static time fault handling in S12ZVM

[pratibhasurabhi]

Hi all,

I have question regarding below point from S12ZVM datasheet,

1.13.3.4 Static Timing Fault Handling
The following Faults and/or errors can occur:
• Desaturation error, Overvoltage, Undervoltage, External fault
The application run-time error is handled by the GDU without CPU interaction. Firstly the FETs are
disabled and the PMF signals switched to an inactive state. To re-enable the operation first the GDU fault
and then PWM fault must be cleared, to automatically re-enable the FET driving at the next PWM
boundary.

As per this point , to re-enable the FET driving, SW should clear the GDU and PWM faults.

In our SW we have cleared the GDU fault(GDUF flag) in initialization setting of GDU.

For PMF fault setting is not done. Reset setting is used.

I want to know, is PWM fault is nothing but PMF fault?

If PWm fault is different than PMF fault then, please let me know what setting is required for PWM fault to enable/disable.

Request you to please share the details of above question as early as possible.

Thanks

[danielmartynek]

Hi pratibhasurabhi,

The PMF fault protection is described in the RM rev2.13, Section 15.4.13.
There are FAULT0-5 mapped on the system level:

Besides that, the PMF module detects Reload Overrun.

Regards,

Daniel

[pratibhasurabhi]

Thanks Danial for the quick reply.

In below part of datasheet, 

1.13.3.4 Static Timing Fault Handling
The following Faults and/or errors can occur:
• Desaturation error, Overvoltage, Undervoltage, External fault
The application run-time error is handled by the GDU without CPU interaction. Firstly the FETs are
disabled and the PMF signals switched to an inactive state. To re-enable the operation first the GDU fault
and then PWM fault must be cleared, to automatically re-enable the FET driving at the next PWM
boundary.

My understanding is,

The PWM fault meaning is the PMF FAULT0-5 shown in above Table 1-12.

Please confirm the understanding.

Thank You!

[danielmartynek]

Yes, correct.

BR, Daniel

[pratibhasurabhi]

Hi Daniel,

As mentioned in below point, to re-enable the operation first the GDU and then PMF fault must be cleared.

1.13.3.4 Static Timing Fault Handling
The following Faults and/or errors can occur:
• Desaturation error, Overvoltage, Undervoltage, External fault
The application run-time error is handled by the GDU without CPU interaction. Firstly the FETs are
disabled and the PMF signals switched to an inactive state. To re-enable the operation first the GDU fault
and then PWM fault must be cleared, to automatically re-enable the FET driving at the next PWM
boundary

We have referred the MC9S12ZVML128 hall sample code for our application development.

We have done the PMF setting as below,

In SW, we have cleared the GDU flag and handled the PMF fault on GDU level(i.e. GDU over curent, VLS under voltge, HD over voltage failsafe are implemented) and its respective GDU flags are cleared.

As per the datasheet, clearing of PMF fault is must.

Request you to confirm that, is it ok if we clear the GDU flags and not clearing PMF fault using PMF register?

[danielmartynek]

Hello pratibhasurabhi,

If the PMF fault detection is enabled (PMFFEN) you can use either Automatic or Manual PMF Fault Recovery.

Please have a look at these sections in the RM.

15.4.13 Fault Protection

15.4.13.2 Automatic Fault Recovery

15.4.13.3 Manual Fault Recovery

Thank you,

BR, Daniel