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Picaxe chip programming

Hello everybody.

I've gotten picaxe 28x1 project board, but now I really want to make my own boards. So I need to program the chips somehow. What is the fastest way to program, lets say, picaxe 18m2? (I would like to use these since they are very functional.)

Also, a few questions :

1. Is it somehow possible to program Picaxe 18m2 chip with my 28x1 project board?
2. I have also got SD21. Would it be possible to connect the "Stereo PICAXE socket" to it and then program the chip?
3. If none of the above are possible, can someone post the simplest scheme for a programming board?


Thank you.


PROBLEM SOLVED. Seems I have bought a crappy stereo picaxe socket, I've got it replaced and everything works flawlessly.


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I build most of my own picaxe boards. Programming them is easy. Your PC's serial port connects to the serial pins on the chip. Every picaxe chip has those input/outputs on different pin numbers (sometimes called leg numbers). So read the manual for your chip.

Since the PC is using much higher voltages than the chip, you need a few resistors forming a voltage divider. The divider is also mentioned in the picaxe manuals. The 12 V from the PC serial out is divided by a 10k and 22k resistor. The picaxe serial input "sees" only 10k / 32k ~ one third of the PC voltage.

The PC "sees" only the 5 V serial signals from the picaxe, but that is plenty.

Other items you need on board: power supply of 5 V, a pullup resistor for the reset pin. Perhaps a reset switch.

Save yourself the head ache. Don't try to stick an 18 pin chip in a 28 pin socket. Chances are you will not get the connections you need. Possibly even damage your chip.

What kind of downloading cable do you have? If you have the USB cable (Axe207) I suggest looking in manual 1 on page 36, where you will find this.

also study page 29! (minimum operation of 18 pin).

I have started to build in the downloading circuit to all my projects so that it is easy to make software uppdates. :)


Unfortunately I am using AXE026 serial cable. But I guess the schematics do not change. Or do they?

The schematics are the same, just remember the 18m2 run on low power (3V).


Does low power means strictly no more than 3V, because I was planning to use my cellphone battery, that is 3.7 volts. If the voltage is too high maybe a resistor would do the trick?

also, I have found "picaxe breadboard adapter" . I am guessing that is exactly what I need, right?

Just checked the manual, this new chip has some features.The chip itself can run on a minimum of 1.8V and a maximum of 3.3V. However, it has an "internal Low Drop Out Regulator, which is automatically enabled when required". Which means that it has an operation range of 1.8V to 5V (3.7V will be fine).

Yes, the only other thing you will need to program the chip is that adapter, or can jus build the circuit your selfe on a breadboard as renkku and rik mentioned.

This chip has many new features, make sure to check them out:


Thank you guys for the help. That 18m2 is one smart-ass chip, I should say :D

I put my resistors on the breadboard, then a set of male header pins. They connect to my PC through this homemade cable adaption.

Note the "documentation" on the flat connetor (that I stole form a computer). It has symbols for GND, "data that way" and "data this way". Because directions "in" or "out" are always relative.

After breadboarding, I solder my components to a circuit board, including the programming pins and resistors. This is the cable that programs all of those boards now.


Yeah, gotta get one myselfe :)

I have tried to program the picaxe on a perfboard using picaxe breadboard adapter and the chip but with no results. The programmer says there is no connection.

my circuit looks like this :

I have also tried putting pull up (4k7) resistor between V+ and serial in, but with no luck.

I guess there is probably some stupid mistake here.