Microcontroller Intermediate
Kit - First Microcontroller Project - Making an LED Blink
Step 1.) The first step is to build the circuit. At
this point you should be familiar with the parts
used. (2 resistors, 3 capacitors, 1 LED). You can
either put these parts together using a breadboard
or wirewrap. This design is intended for use with an
Atmel 2051 microcontroller (a 20 pin version of the
8051). Most microcontrollers (such as a normal 8051
or 8751) can not handle the current required to turn
an LED on and off but the ATMEL part has this
capability.
Vcc
= 5V and Gnd = 0V
After building the circuit
you should have something that looks like the
picture below (click the picture for a really big
version!)
The only thing we want to
do with this project is to make the LED blink. By
doing this, you will be able to learn the basic
process of compiling a program written in assembly
language and then programming the resulting file
into the microcontroller.
First we will assume we already have the assembly
code written. ledtest.asm is the assembly language
program we are going to use. (This file is included
with TASM )
Step 2.) Compiling the Code
Move the assembly language program (ledtest.asm) to
the directory where you have TASM. Bring up a DOS
prompt, change to the directory where the TASM files
are, and compile the code using the command
tasm -51 ledtest.asm ledtest.hex
This will create a file called ledtest.hex.
Close the DOS prompt window now.
Step 3.) Downloading the code to the
Microcontroller.
Make sure the serial cable and the power supply are
connected to the PG302 programmer.
Put your microcontroller into the PG302 programmer.
Run PG302.
From the Setup Menu, select the type of device
(microcontroller) you are using
From the Setup Menu, select the Comm port you are
using.
Press PROGRAM DEVICE.
Press BROWSE.
Find ledtest.hex and click on it (single click).
Press OK to select the file.
Press OK to program the file into the
microcontroller.
Now the program should be loaded into the
microcontroller.
Make sure the power is off for the circuit you have
built.
Move the microcontroller back to the circuit you
have built.
Turn on the power to the circuit. If the LED starts
blinking, then you have successfully built your
first microcontroller project.
The parts for this kit are included in the
Microcontroller Beginner Kit. See part 2 for parts
list.