6) GETTING STARTED WITH MICROCONTROLLERS
In order to get started with microcontrollers, several factors need
to be considered.
- cost
- convenience
- availability of development tools
- intended use
The hardware described in this section is readily available,
affordable, and is easy to find software for.
Many manufacturers offer assembled evaluation kits or boards which
usually allow you to use a PC as a host development system. Among
some of the more popular evaluations kits/boards are:
Parallax Basic Stamp
This is a small single-board controller that runs BASIC, and costs
only $39. A SIP version for only $29 is also available. THE 256
byte EEPROM can hold a program of up to about 100 instructions.
The BASIC Stamp Programming Package is a complete development
package for only $99.
Parallax, Inc., 3805 Atherton Rd. 102, Rocklin, CA 95765
(916)624-8333 Fax: (916)624-8003 BBS: (916)624-7101
email: info@parallaxinc.com
Motorola EVBU, EVB, EVM, EVS
A series of very popular evaluation/development systems based on
the 68hc11. Comes complete with the BUFFALO monitor and varying
types of development software. Commonly used for university
courses.
Motorola 68705 starter kit
Motorola supplies a complete development system, -- software,
hardware, simulator, emulator, manuals, etc for just $100.
Dallas Semiconductor DS5000TK
The DS5000TK allows evaluation of any DS5000 series device in any
existing application without circuit changes. The included
DS5000T plugs into the supplied serial interface pod which
provides a connection to a host PC. A target cable connects the
pod to the target system. Programs can be downloaded directly to
the chip (no EPROM programming!) using the built-in serial loader.
(With Dunfield's Development System, you end up with a cheap
"pseudo-ice". Dunfield also has a circuit if you want to build a
similar device.)
Philips/CEIBO DS750
For $100 (from Philips, from CEIBO the price is $250), you get a
"pseudo-ice" for testing your code in-circuit. Based on the
low-end Philips 87c75x parts. Allows source-code debugging in
assembler (included), C, and PL/M, with an interface similar to
that of Borland's Turbo Debugger. Very popular with students and
consultants for experimenting with 80c51 code. Includes a VERY
NICE book which describes the theory of operation of the board
itself, and includes a good number of experiments that you can try
for yourself. Philips sold nearly 10,000 of these boards in the
USA (and 5000 in Europe without even advertising).
National Semiconductor's EPU
The COP8780 Evaluation / Programming Unit (EPU) offers designers a
low-cost ($125) tool for an introduction to National's COP8 Basic
Family of 8-bit microcontrollers. This development tool gives you
an inexpensive way to benchmark and evaluate microcontroller code
in realtime. With its built in MIRCOWIRE/PLUS interface, it can
interface to numerous MICROWIRE/PLUS devices such as EPROMS,
EEPROMS, D/As, A/Ds, DASs, and others, to give a full featured
system. The system includes the EPU board, assembler and debugger
software, sample code, very limited C compiler, wall power supply,
documentation, and a really great box :-).
Zorin BOTBoard
The BOTBoard is a low cost and powerful single board computer
based on the Motorola HC11E series Microcontroller. The Zorin
kits make it easy to create many types of computer controlled
applications. Get the optional servo motors to create walking
machines, robotic arms, animated art and more! Program the
on-chip memory from any computer or terminal using the Buffalo
monitor, or use the PC software included with the kit. The eight
page assembly manual includes example code to operate the servo
motors.
Zorin / POB 30547 / Seattle, WA 98103-0547
(206)282-6061
zchris@eskimo.com
In addition, several chips provide a similar capability if you are
willing to spend a bit of time wiring up a simple circuit. A few
chips worth looking at are:
Motorola MC68HC11A8P1
Contains Motorola's BUFFALO monitor which has the same
functionality as the one on Motorola's evaluation boards. A
working system can be built with this chip and a Maxim MAX-232.
You can talk to it with a PC or Mac over a 3-wire RS232
connection. It is easy to load and run anything you want in the
on-board RAM and EEPROM. You can even use subprograms in the
BUFFALO monitor after getting a listing from Motorola's BBS or ftp
site. This BBS/ftp site also has freeware assemblers to make a
complete development environment cheaply and quickly.
Intel 8052AH-BASIC
This popular chip with hobbyists is another easy way to get
started. You can download high level code from your host. The
disadvantages are that you can't get away from a multi-chip
solution, the code is noticeably slow, you have to buy an MCS
BASIC manual, you are detached from the inner workings, there
aren't many on-chip goodies like A/D, and you can forget about
running off of a battery.
Dallas Semiconductor DS5000/DS2250
These are well suited even for electronics ignoramuses (ignorami?)
such as myself. All you need to add is a crystal and two
capacitors to end up with a working system. These chips come
complete with non-volatile RAM in the form of static RAM (at least
8K) backed up with a lithium battery. Everything is saved -
program, data, and bugs ;-).
MicroChip PIC '5x series
With only 33 instructions, this chip is definitely easy to use!
Using Parallax's assembler, the instruction set is ** MUCH ** less
intimidating than MicroChip's opcodes! These chips simply need
power, ground, and 1 of 4 different timing circuits. Doesn't get
much easier than that! With I/O pins that are beefy (25mA per pin
sink, 20mA per pin source) and drive both high and low,
interfacing is super easy. It's great to hook LEDs and such
directly to output pins with only a resister in-line!
You can search for free software for development, but you often get
what you pay for. What is sorely lacking in freeware is technical
support. Several packages are available that provide complete
development environments for some of the more popular
microcontrollers. If you want to be productive right away, think
about investing $100 or so - it'll be well worth the price!
I've been playing with the Dunfield Development System lately (on the
8051), and it's really quite nice. I've also heard many good things
about it from others. It includes a near ANSI-C compiler, run-time
library with source, assembler, ROM debugger, integrated development
environment, monitor with source, utilities, and other extras.
Although not freeware, the low price ($100), the features, all of the
extra goodies, and the good reviews make this a package worth looking
at. Also, if you're interested in working on more than one family of
microcontroller, Dunfield supports a wide range. This means only
needing to learn one system, instead of many. The following chips
are supported: 6805, 6809, 68hc11, 68hc16, 8051/52, 8080/85, 8086,
and 8096. A package including a simulator and a resident monitor
debugger are also available for the 8051 for $50.
Dunfield Development Systems
P.O. Box 31044, Nepean, Ontario K2B 8S8 Canada
(613)256-5820 Fax: (613)256-5821
Email: ddunfield@bix.com
A decent C compiler for the 68hc11 comes from ImageCraft. This
package, which runs under DOS and OS/2, includes a near ANSI C
compiler, assembler, linker, librarian, ANSI C functions and headers,
and 90 page manual. The current release is version 1.02 of their
compiler. The price is just $40. Initial feedback on this compiler
seems promising. The pre-release versions are already in use by many
of you, and will still be available as freeware.
ImageCraft
P.O. Box 64226, Sunnyvale, CA 94086-9991
(Richard Man) imagecft@netcom.com
Another low priced ($100) C compiler comes from Micro Computer
Control. Cross compilers running under DOS are available for the
8051 and the Z8 (including Super-8). This package includes a C
compiler, assembler, linker, librarian, and extensive printed
documentation. A simulator/source code debugger is available for an
additional $79.95.
Micro Computer Control Corporation
PO Box 275, 17 Model Ave., Hopewell, NJ 08525
(609)466-1751 Fax: (609)466-4116 BBS: (609)466-4117
Email: 73062.3336@compuserve.com
C isn't the only development system available (yeah, I know that's
hard to believe) - good solid Basic and Forth development systems are
also available. Refer to the appropriate FAQ for the microcontroller
that you are using for more information on free and commercial
development systems.
If the Microchip PIC is your game, then check out the Parallax tools
(available on their ftp and web sites). All Parallax software is
available free of charge to all takers! This includes PSIM (a PIC
simulator), PASM (an assembler for '5x parts), and PASMX (an
assembler for 'xx parts). These are the full commercial versions,
not hobbled in any way!