Which Self Check mode of CCM-R4 does bit 16 of CCMSR Register is SET?

Pashan,

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He will be back to you shortly.

Pashan,

Bit 16 of CCMSR (CMPE) is set on the following conditions:

1] An compare error happens in normal mode (lockstep) while CPU is running, or
2] CCMR4 is in self test error forcing mode and CPU is running. In debug mode, self test error forcing mode does not set bit 16.

A system reset or writing on to this bit will clear it

Hello Jean-Marc,

In the previous mail : http://e2e.ti.com/support/microcontrollers/hercules/f/362/t/103149.aspx

You will see the following TEXT by Sunil Oak -- Posted by Sunil Oak on Jan 28, 2012 4:50 PM

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The CCM-R4F module has four unique modes, each with its own purpose:

1. Self-test error forcing mode: this mode ensures that any error during the self-test of the CCM-R4 compare logic itself is actually flagged as a self-test error in the CCM-R4 status register. This also sets the CCM-R4 self-test error flag in the ESM (group 1 channel 31). The application must look for these error flags to become set and then clear them. The compare error flag is not set in this mode.

*************************************************************************************************

You are saying that CMPe [Bit 16] is set when

MKEY = 0x0F -- Self Test Error Forcing Mode

It is completely opposite of what Sunil Oak has mentioned in previous LINK.

Please let me know who is correct.

Thank you.

Regards

Pashan

Hi Pashan, From my understanding, Self-test error forcing mode will not set the CCMSR CMPE compare error flag. The error forcing and the selft test error forcing modes will test the ESM path in a different way. The self test error forcing mode will flag ESM1.31(CCMR4-selftest error) and the error forcing mode will flag both ESM1.31 as well as ESM2.2 (CCMR4 Compare Error).

Again, this is my understanding from empirical results.  This topic has come up recently and there will likely be clarification added to the next TRM update.

Regards,

Eric

Hello Jean-Marc,

Can you please provide a short DEMO Project with CMPE bit set for CCM-R4?

That will help me a lot.

Thank you.

Regards

Pashan