[SOLVED] MPASM ..SO I FINALLY PUT A 20 MHZ CRYSTAL IN ...some surprises PIC16F1784

[techristian]

SO I FINALLY PUT A 20 MHZ CRYSTAL IN

The big surprise was that I had to put at least 20 NOP instructions in to make the program work properly....and of course it ran much faster.

Some places seemed more critical for NOPs and other places could even be affected NEGATIVELY when NOPs were inserted??

I understand there is some latency issues with PIC but this surprised me.


Dan

 

[123jack]

Perhaps if you gave some info on what you are talking about?
Have you accidentally created a thread instead of replying to one?

 

[techristian]

First of all, I'm talking about a PIC CHIP. That should be evident, from the title. Secondly I have discovered that some commands have latency and need NOPS either a) before executing or b) after executing.

I was hoping that someone here had experienced this and could list the PIC16F1784 commands which needed these NOPs.

It doesn't make sense to have such a high clock rate if I need to code in so many NOPs.

Dan

 

[techristian]

MY BAD

_PLLEN_ON ...that was the problem. When I made it _PLLEN_OFF everything worked properly and 40X as fast as with INTOSC .

Dan