K10 FTM2 Set/GetOffsetTicks problems

[MarkP_]

Hi,

the problem is that SetOffsetTicks doesn't work always. Function is called about once a second.

Quite often the new value doesn't go to HW, and readback by GetOffsetTicks returns the previous CnV value.

is there any knwon issue ni HW or PE-generated code?

Does FTM2 write erroneously the earlier value from cache register?

Checked the generated C code and disassemble-file, seems to be OK.

CPU revision is 0N96B, errata doesn't mention this kind of problem.

Added test counters:

TMR_SetCount[ChannelIdx]++;

TMR_GetCount[ChannelIdx]++;

They show that Set/Get functions are called correctly.

~Mark

[ProcessorExpert · Accepted solution]

Hi,

The problem is  probably that the register is buffered - that's why you  don't immediatelly read the written value, because you read the current value of the counter not what you wrote. When the register is written, the value is applied after te buffer is synchronized to the counter. It depends on the settings but the register should be synchronized after the end of the period. To force synchronization, it's necessary to disable and enable the timer again.

best regards
Petr Hradsky
Processor Expert Support Team