I need help with the Logic Analyzer in MPLAB 8.92 please

[ljcox]

I can't work out how to change the scale of the Logic Analyzer.

The Help was no help.

The pulse shown on the attachment is the first of many. I would like to see the complete waveform.

Any assistance will be appreciated.

Len

 

[hevans1944]

Is there some reason you haven't upgraded to MPLAB X IDE instead of using MPLAB 8.92? If you upgrade (it's free of course!) then you might want to read this Microchip forum post. Ummm,,, you did visit the Microchip forums before posting here of course... riiiight? Word on the street is the logic analyzer and simulation (software version at least) are not worth wasting your time for real-time, real application development. Perhaps the REAL ICE hardware version is more up to snuff, but I have always avoided simulators and emulators because of their disconnect from real world operation. Also, did you notice in the screen capture you posted, that the trigger is set to the end instead of the start? Perhaps this is a factor in what you capture...

I haven't fired up any of my hobby and development PICs since last summer, while still living in Dayton, OH. I would like resume my involvement with PICs "real soon now" but still haven't recovered from our move to Florida in December 2016. For now, unless someone else jumps in to help you, I would suggest you join a Microchip forum and ask questions there. The Microchip development community is very large and extremely helpful if you can express your problem clearly enough.

 

[ljcox]

Thanks for the response.
There are 2 reasons why I did not upgrade to MPLAB X IDE.
1. I did not know about it. 2. I'm happy with 8.92. It does everything I need.
I did not think of the Microchip forum. I'll try that.
I set the Trigger to Start initially, then to Centre & then End. Each one gave me the same result.
It's about 3 years since I last did a PIC programme. I used the Logic Analyser successfully a few times, but the waveform was relatively short in those cases.
Len

 

[hevans1944]

I'm happy with 8.92. It does everything I need.

Well, except the logic analyzer doesn't appear to work properly. I've never tried to use the logic analyzer, so am totally unfamiliar with its idiosyncrasies. Apparently there are many, mainly because it is OLD and Microchip hasn't put forth any effort to support it. If I even get involved again, I'll fire up whatever the latest version of MPLAB X IDE happens to be and try to use the "logic analyzer" on a simple project.

Don't hold your breath waiting for me though. There are several people lurking here with far more hands-on experience with PICs and the MPLAB X IDE. Have some patience, maybe describe the problem in more detail, and perhaps one of the lurkers will jump into this thread with good advice.

BTW, what ARE you trying to DO with your PIC? Which PIC are you using? How much code have you written so far? Are you using a high-level language or assembly programming? A high-level block diagram could be helpful for us to understand what you intend to accomplish... just sayin'... more information doesn't hurt, and irrelevant info will be ignored as soon as we figure out what is relevant and what is not. Please post here if you find out a solution or a "work around" to your problem with the Microchip Logic Analyzer.

 

[ljcox]

One of the posts in the link you gave me pointed me in the right direction.

He said to change the buffer size. I opened Debugger > Settings > Osc/Trace. The Buffer size can be set in this window.
I increased the Buffer size & also reduced the Oscillator frequency from 4 MHz to 40 kHz and then altered the timers accordingly.
Thus I was able to see the whole waveform. So, as far as I can see, the Logic Analyser works as expected.
EDIT
I'm using a 16F84 to generate pulses to test another programme I've written. The 16F84 generates dial pulses (i.e. it simulates a telephone dial). The other programme (using a 16F684) receives the pulses & regenerates them at a slightly faster rate. It was tricky since the outgoing pulses are being sent while the incoming pulses are being received.

Thanks for the info.

Len

 

[hevans1944]

Certainly glad you got that sorted! Do the logic analyzer wave forms act according to your conception of what they should do? Is the logic analyzer of any help in debugging or testing your program?