PIC programming...

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:shock:

Yes I mentioned having issues with PIC micros and their quirks. Thats part of the reason for choosing Atmels. I haven't had any real problem with the Atmel parts themselves.

I have an STK500 at work and use it to load proggys onto the MCUs in circuit. man I love being able to do that..

I have been looking at code for these atmels for a while and it *sort of* makes sense. I can hack it to do slightly different things but if a blank page was set before me I wouldn't have the slightest clue where to start and/or why.
 
Hi,

I have some experience with PIC microcontrollers. Lately I have been using PIC16F876a. The load capacitors of the oscillator sometimes need some adjusting to make the microcontroller start up properly, but as soon as that is sorted out, it works like a charm.
I program exclusively in assembly language and I use a MPLAB ICD2, which I highly recommend to debug your application.

For software routines I highly recommend www.piclist.org

R
 
While ago I used the STK-200 AVR kit to reverse engineer Peavey Studiomix firmware (which used 8031 uC). For some reason I couldn't get the software I wrote on GNU AVR C to work properly. First I found out that the loop optimization in C->ASM phase made my code disfunctional (so remember to use the "volatile" word where you don't want the compiler mess with your logics). Anyway, that didn't solve the problem in reading the data sent from PC to STK (the AVR program froze suddenly, and it was not a watchdog problem though it looked like it). After all I was able to program the Peavy EEPROM using some hack, but the AVR platform was not convincing me. The PIC soft I've written (a keyboard scanner and a simple MIDI drum brain) were working fine though.
 
FWIW, DIYStompboxes has started a forum for µC's and DSP. It's still ramping up, so it's a good time to drop in if you're interested in that sort of thing.
 
Cool thread. I hadn't looked into PICs for quite some time. When we were programming midi applications at the university, it was pure C, not object oriented or anything. Wish I could remember what the model we used was. It was dead simple and with a good freely modifiable development board with LCD included.

Speaking of which, I had a quick look at this: http://www.elecdesign.com/Articles/Index.cfm?AD=1&AD=1&ArticleID=4766

"Reconfigurable Analog ICs Herald An Era Of In-System Programmability"

Looks extremely interesting. I mean, wouldn't you like to program and edit real analog filters on the fly? I wonder why no synth manufacturer has jumped on that. It would be like SID, but you could change the architecture on the fly.
 
[quote author="Kingston"]Speaking of which, I had a quick look at this: http://www.elecdesign.com/Articles/Index.cfm?AD=1&AD=1&ArticleID=4766

"Reconfigurable Analog ICs Herald An Era Of In-System Programmability"

Looks extremely interesting. I mean, wouldn't you like to program and edit real analog filters on the fly? I wonder why no synth manufacturer has jumped on that. It would be like SID, but you could change the architecture on the fly.[/quote]

Those folks pitched to Harman hard, and in the end I was less than impressed. For one thing they rely extensively on switched cap architectures, which are much better than they used to be but are inherently noisy (I queried the PhD CTO (or whatever the f*** his title was) about charge pumping noise in MOS switches and the low-frequency noise spectrum associated with it, and he replied that as he recalled you only got 1/f noise when current was flowing. Back to school for you, buddy boy :razz: ).

As far as I can assess, their stuff appeals to people who can't do analog design and have low-volume apps. As soon as you are doing any kind of volume there are much cheaper and higher perfomance tailor-made alternatives, even if you insist on the programmability feature.
 
I just started learning how to program pic's myself. I 'found' a couple of SID's and when I looked around trying to figure out what to do with them i found the www.midibox.org project and got curious about how all that stuff works.

I just built my own version of the tait-programmer and it works. I burned my first "blink a led" program into a PIC12F675 (nice 8-pin dip package pic) and right now I'm trying to figure out pic-assembly.
 
[quote author="bcarso"](I queried the PhD CTO (or whatever the f*** his title was) about charge pumping noise in MOS switches and the low-frequency noise spectrum associated with it, and he replied that as he recalled you only got 1/f noise when current was flowing. Back to school for you, buddy boy :razz: ). [/quote]

haha. oh dear.


[quote author="bcarso"]As far as I can assess, their stuff appeals to people who can't do analog design and have low-volume apps. As soon as you are doing any kind of volume there are much cheaper and higher perfomance tailor-made alternatives, even if you insist on the programmability feature.[/quote]

My initial impression was that these would only be good as "lofi" tools, ie. freely programmable synth oddities. SID isn't exactly a triumph of s/n (it was back in the day) and known for its lack of on-chip limitations, or errors. I kind of appreciate gadgets like that, and I wouldn't mind an open ended SID type tool. I don't think the point of this was to make the design phase any easier, but allow for certain flexibility that hasn't been possible before. Instead of brute force methods, or restricting the end user, you could just let THEM change things on the fly.


which is why I'll probably grab one of their dev boards sometime in the near future.
 
I have been using the Microchip line products fairly successfully. All chips utilize the same basic architecture so once you learn the op codes for one chip, you can easily pick up another. The basic differences generally have to do with the different peripheral devices in each chip line. Microchip also offers free IDE tools such as MPLAB found here:

http://www.microchip.com/stellent/i...E&nodeId=1406&dDocName=en019469&part=SW007002

I built a printer port connected programmer (similar to the David Tait design) for the 16F628a and use it with the ProPic2 software. Here is a link to a page that has several useful links:

http://www.bobblick.com/techref/projects/picprog/picprog.html

I program these mostly in machine language, mainly for efficiency of coding, since a large amount of the code space is used to provide for the operator interface of the device. The other major development task is designing interfaces using serial shift register/driver chips to expand the number of available inputs and outputs.

Here is a company that sells a line of prototyping PC boards for various PICs. They also have software and parts:

http://www.hobbyengineering.com/CatPCPROTO.html
 
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