PIC microcontrollers

I thought I would put some of my info on PICs in one place.

For thoes of you who are not framilliar with a PIC they are a microcontroller made by Microchip.

The most commonly used one is the 16F84. This is an 18pin device that is flash programmable. This means that you can erase the chip using the programmer so that you dont have to use(and wait for) a UV eraser.

Most of my designs are around this chip because most of the Freeware out there uses this chip and if you want to use another chip it costs more.

Problems:

One problem I had with this chip is that the surface mount version is a 16F84-20 and the dip version I was testing with was a 16F84-10. According to the spec sheets the only difference is the maximum clock speed is 20Mhz on the newer chip. I was unable to program the newer chips with the software I was using. I guess some software uses less than optimal timing routines and the newer chips are picky about the timing. Well this would not have been a huge deal but the surface mount chip was a new design and was surface mounted in circuit. I went round and round and finally ordered a 16F84-20 that was the DIP style and it wouldn't program. Then I had something I could troubleshoot and found software that could program either chip.
This software is available from IC-prog .

Programmer:

Write program in C-->Compile into assembly language-->Assemble into machine code-->Program device

The first thing you will need is the assembler that comes from Microchip MPASM.
You can get this as part of a suite of programs in the MPLAB IDE but thats like 11.5Meg.
If you have a slow connection you may just want to download the MPASM program(2.3Meg).
These can be downloaded from Microchip for free.

And unless you are going to program in assembler you will want another program so you can write it in a higher language.
I chose the C2C compiler that allows me to program the device using the C language.
The free version will only program the 16F84 and is available from C2C.

Now that you have a compiler and assembler you need something to program the device.

I used the software available from IC-prog.

I used a version of the Tait "Classic" programmer shown below.

LINKS

Microchip - Makes the PIC microcontroller- Data sheets are available here- Or order on CDROM

Digikey - Online store carrying PIC microcontrollers

Newark - Online store carrying PIC microcontrollers

C2C - This site has a C compiler for the PIC

IC-prog - The programming software I use. And schematics for programmers.