the software presented in this post is buggy, windows only whitout the possibility of capturing more than “one file line” length (save a captured stream and have a look at it from text editor), able to trigger on one channel.

tfla-01 from berlios was written in 2005, is open source, multiplatform (QT GUI, qt guis are much more comfortable than a few years ago), able to trigger every channel and ABLE to capture for a longer period than just 40ms (24 hours), allowing analysis of command/signalling sequences longer than 40ms.

no, i am not the author of this software, i just needed an lpt capture programm capable to capture data for more than 40ms.

yes, i know that this hackaday article is listed before tfla whit terms concerning this theme.

and no, not only because “the fabulous logic analyzer” is open source i am not interest in
counsel the author about search engine optimisation.

The difference between those linked in this article and comments is that mine is standalone, i.e. requires no PC.

Nice design. I wonder if you get subtle flickers when updating the PWM values. I’ve found in my designs on the 14bit pics, that I have to update the PWM when my ” 1 byte cycle counter” wraps to zero rather than immediately. You are clocking at a higher clock rate (I use 4-8mhz internal clocks with up to 10 PWM channels), so your design may not be so sensitive.

Recently, i’ve given up on the PIC and it’s goofy architecture and moved to the Cypress PSOC parts. They are really neat with dedicated digital and analog blocks. You can set up up to 16 PWM (actually I use pseudo random bit sequences, which have less flicker) outputs, and the C compiler is really reliable vs the buggy stuff i’ve experienced w/ the pic (though the PSOC compiler generates crap code). The PSOC has it’s own shortcomings, such as a really inefficient CPU, but the digital and analog blocks more than make up for it b/c stuff is done in HW vs SW. PSOC is really fun, esp when u wrap your head around it’s way of doing things.

http://www-user.tu-chemnitz.de/~heha/bastelecke/Rund%20um%20den%20PC/USB2LPT/ul-15.htm.en

then you will have a spare lpt port.

I think it would be nice to add some kind of playback support. Since those pins on the parallel port are bidirectional, it should be simple enough. Time to pull out my soldering iron!