PICAXE programming

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As I mentioned in a comment, I've been playing with microcontrollers these days. I started out with a BASIC Stamp2 system which was great and very educational, but quickly ran into its limitations -- the main one being financial, each STAMP is around $40-50 which limits its applicability.

But the advantage of the STAMP is that it's very easy to program (in BASIC!) and that it has the ability to pulse PWM to control RC servos, which makes it ideal for EV projects.

On my explorations for a cheaper microcontroller, I came across the open source Arduino which was fantastic except that it was still expensive ($20 / chip for the cheapest) and the programming environment was more fidgety that I liked.

The solution appears to be PICAXE. The cheapest one is $3 / chip (wow!) and it can do full time PWM as well as has a A/D converter right in the chip. And its fully scalable as well. The BASIC programming language seems very similar to the STAMP and runs on Macs, Linux, and MS.

$3/chip for the 8M means that I'll be able to place them everywhere! Cheap is good!

Ultimately, I could roll together my own ESC since the basics of PWM are fairly simple with these microcontrollers -- just feed their outputs to some MOSFETs.

The only tough thing is that the RC brushless motors I use don't have hall sensors on them. It'd be much easier to make a PWM brushed motor ESC...

Oh... and if you want to get Stamps, Arduinos, or PICAXE chips, you can get them at SparkFun -- which is geek heaven.

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I love to use PICAXE too..very simple and cheap. I'm a desktop software engineer but i want to learn more about hardware and electronics, so PICAXE is a great start for me.

It should be noted that with PICAXE and some of the others like Basic Stamp that the code is interpreted on-chip and not compiled in to native op-codes. While this does make the chips easier to interface and the language simpler, it may be a good idea to use the PIC chips directly since you take a severe hit in overall speed, overall program size and you lose some IO pins. I only state this because when you're watching for real-time events such as input from a hall sensor from a fast spinning motor, it's easy to miss pulses from long execution times.
Microchip sells the PICkit2 programmer for about $50 and you can use their free assembler. If you use the high performance 8-bit MCU's you can get the free student version of the pic-18 compiler. otherwise you can use PICBasic, which supports a number of the PIC lines up to mid-range for about $100 or you can get the Pro version for $250 which supports the majority of the chips.
Anyways, there's something to be said for microcontrollers. They have all kinds of functions and it really opens the door to be able to build damn near anything. They kick ass! :)

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This page contains a single entry by Karen Nakamura published on August 21, 2009 4:31 PM.

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