Getting Started with PICs

Introduction

This dicusses how to get started in developing PIC applications using the 16C84.

The 16C84 is particularly attractive as it may be erased and programmed electrically.

At a minimum you will need some PIC16C84 devices, a clock, software to assemble and simulate your code and a programmer along with the necessary software to download the .hex file and program the device.

In the following I discuss where each of these may be obtained.

16C84.

The 16C84 is available from DigiKey (http://www.digikey.com). I have standardized on the 16C84-04/P which at the time of this writing was $6.48 in single unit quantities. This is an 18-terminal DIP with an operating temperature of 0 to 70 degrees C.

Another possible source is ITU Technologies in Ohio (http://www.itutech.com).

Clock.

You will need a clock oscillator, crystal or resonator. Over my life I have wasted a good many hours because a crystal refused to do its thing. On the other hand I have always had good luck with the self contained clock units that are packaged in a "can" having four terminals, and thus decided to standardize on using TTL clock oscillators.

These are available from DigiKey as Part X107-ND, 4.00 MHz TTL clock oscillator, $3.38.

Note that I keep 16C84-04/P ICs and 4.0 MHz on hand for my students and you may order from me at the following prices;

	16C84-04/P			$6.00
	4.0 MHz TTL Clock Oscillator 	$2.50

	10 10K, 10 330 Ohm, 5 LEDs	$1.00

This is everything you need for prototyping simple programs.

My goal here is to help someone get started quickly and inexpensively. Thus, please order no more than three of any of the above.

Assembler and Simulator.

One approach is to purchase the PICSTART Plus Programmer (DigiKey #DV003001-ND, $199.00).

This package includes a programmer capable of programming all PIC16C and PIC17C devices. It includes a ZIF socket, power transformer and RS232 Cable.

The package also includes Microchip's MPLAB which is a windows based program which permits you to edit, assemble (MPASM) and simulate (MPSIM) all in an integrated environment. It also includes manuals for the assembler and simulator.

One advantage of the PICSTART Plus programmer is that the software associated with the programmer is integrated into MPLAB.

If you decide not to purchase the PICSTART Plus system, you will need the MPLAB software and users manual. It is available free of charge from Microchip at http://www.microchip.com Go to "Tools".

Programmer.

If you decide not to purchase the PICSTART Plus Programmer, you will need a programmer.

The programmer isn't much. Most use the parallel port and consist only of +12 and +5 Volt supplies, a 7407 hex inverter with open collector outputs and two transistors.

There are many many designs on the WWW and a good starting point is Ormix in Latvia. (http://www.ormix.riga.lv).

However, I place some value on my time and ordered a PIC-1A from ITU Technologies (http://www.itutech.com). The kit is $39.00 and includes a well made printed board, all of the parts, a power adaptor, a cable to connect to the parallel port and the software to download the .hex code and program the device. A ZIF socket is available for another $9.00.

I had a student assemble the kit and she was using it to program devices within two hours.

Note that control of the ITU programmer is from DOS can not be done from the MPLAB integrated environment. But, then again, how hard is it to toggle between MPLAB and DOS!

Good luck!