Getting Started with PICAXE Microcontrollers
If you are interested in getting started with PICAXE microcontrollers, the following project is an easy way to do so. First, download the free Programming Editor software from Revolution Education and install it on your PC. A large amount of documentation is included with this software, and is available under the "Help" menu. Look for the "Getting Started" manual - it includes all the information you need, and then some! Also, download the PICAXE BASIC Summary for beginners to get an idea of the range of powerful commands in PICAXE BASIC. Next, assemble the following pieces of hardware, many of which are available on this site (see the "Products" Sidebar).
For parts that I don't carry, I have included links to Radio Shack part numbers where possible. Of course, most of these items would be much cheaper ordered from Digikey, Jameco, Mouser, or any of the various "surplus electronic parts" suppliers easily found on the internet with a quick Google search.
Parts List:
- Breadboard and jumper wires
- PICAXE-08M Microcontroller
- An LED and a 330 ohm current-limiting resistor or a "resistorized" LED
- A straight-through serial cable (DB-9, Male to Female) to connect to your PC
- A female DB-9 connector for the programming adaptor
- Two resistors for the programming circuit: 10k and 22k
- A two or three-AA battery pack or a regulated 5-volt supply
Never apply more than 5-volts to a PICAXE chip!
Construct the programming adaptor by soldering three wires to the female DB-9 connector as indicated in the following Circuit Diagram. Assemble the circuit as shown below and check the photo to be sure your circuit is wired correctly.
Circuit Diagram:
Circuit Photograph
Once you have the circuit assembled and double-checked, connect it to your PC using the straight-through serial cable, type the following program into the Programming Editor. Make sure you have chosen "08M" and the correct serial port under the View-Options menu, power-up your PICAXE circuit and download the program - it should automatically start to run. By the way, anything following a semi-colon in the program listing is a comment. Comments are ignored by the PICAXE interpreter, so they can be omitted entirely. However, they do make the program more understandable, so they are very helpful!
Program Listing:
; ==== Hello.bas =======================================
; This program runs on a PICAXE-08M at 4MHz
; and blinks an LED on output1 (pin 6).
; ======================================================
; ==== Constant Definitions ============================
symbol LED = 1 ; LED on output1 (pin 6)
; (with a 330 ohm resistor)
; ==== Beginning of Main Program =======================
main: high LED ; turn on LED
wait 1 ; delay 1 second
low LED ; turn off LED
wait 1 ; delay 1 second
goto main ; do it again, forever
If you have trouble, go back and re-check all your wiring. If the Programming Editor doesn't "see" the PICAXE-08M, carefully re-check the connections to the programming adaptor. Also, be sure the flat edge of the LED is connected to ground, or it won't light at all (even if everything else is correct). If all else fails, send me an email (Ron@JRHackett.net) describing the problem, and I'll see if I can help.