lpcware

SCT MATCHMEM Problem/Question

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by rlund on Wed Dec 02 15:55:57 MST 2015
Setting the MATCHMEM bit in the SCT peripheral isn't acting quite as expected. 

There is a case with a match event, where we are interested in knowing if the match has already occurred prior to entering the state where it is activated.  Basically, if the count is equal or greater than the match value, we want  the event to be triggered.

The thought was that the MATCHMEM bit would achieve this result for us.  However, when the MATCHMEM bit is enabled, the event is being triggered upon entering the state, BEFORE the match value is reached.  In other words the count is still less than the match and yet the event is triggered.  This is not what the documentation states should happen.

Yes, the counter is counting up (not down), and isn't setup to be bidirectional.

Any thoughts, are we missing something?  Tried doing a capture on the count for the event in question, and found that the capture value from the count was indeed less than the match value that was setup.

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