Let's Make Robots!

Serial communication gives weird readings

Hey guys,

With the recent discussions in the shout box, i was inspired to play around with sending "orders" to my picaxe with the serial connection.

No problems with it, it is all just simple RS232, BUT something seems to be up.

Every now and then, my picaxe will claim it has received something different than what i sent. Mostly it interperts it correctly, but sometimes it doesn't.

So if i send an 'r' it might read it as a 'q' then as a '?' and then, the third time, as an 'r'.

Is this some common error due to something i have done wrong?

control motor speed

This must be a dumb question, but isn't it possible to control the speed of a motor? I am playing around with the picaxe 28, and as far as i can tell, there is only on/off. I had imagined i could control how much power went through to the motor, hence controlling its speed.

Robot lawn-mowers and border control


There are all these robotic lawn mowers. The ones i've heard of here, detect the edges of your lawn, by a wire you place there.

Does anyone have any idea how this work? How does the robot detect that is above the wire?

Female header pins

Hi all,

I've been reading the 'start here' a couple of times, and it suggests to get these male header pins, which you can then solder onto your board.

I've managed to find some at techsupplies.co.uk (since i'm in Denmark, i prefer EU shops).

BUT, what about the female version? I have not been able to find them anywhere. Is it not possible to buy some, and attach them to some cable yourself, rather than buying cable with them already on?