SparkFun Forums

[pmeyeratdatest]

Hi:

In reviewing the help guides and the forums for the use of the 'drscan' command, I seem to be missing something.

I'd like the ability to specify to drscan a chain that can be up to 1000 bits in length. According to the documentation, chain variables should only be at most 32 bits. If I wanted to specify 1000 bits, what should the drscan syntax look like. I also need to see all 1000 return bits as well.

I can write wrapper code to chunk my 1000 bits into 32, but some guidance on how the arguement is to be constructed and how the return buts are to be reassembled will help.

Many thanks!!

Peter

[pmeyeratdatest]

Just adding to this:

One example I saw had the drscan parking on the drpause state. If at most 32 bits can be executed in one drscan command, will the openocd system that is parked on 'drpause' state go directly back to the drshift state without going through updateDR and RTI?
Should a long shift patterns be chunked into 32 bit writes with the state machine landing on drpause until all bits have been shifted through, and then proceeding to RTI state at the end?

Thoughts?

Peter