Let's Make Robots!

Bluetooth HC-05 not working


I just got my bluetooth HC-05 module from ebay today. I soldered all the essential wires (Vcc,Gnd,LEDs,RX/TX) properly and connected it to a 3.3 volt supply. but when I switched on the power, nohing happened.

Can't program picaxe 20m2


Two days ago, i downloaded a simple debug ADC program onto my picaxe 20m2 to get adc values from an IR phototransistor. Code: main: readadc b.3, b0 debug goto main The program downloaded successfully and a window opened showing the adc values. Then I closed that debug window and made a few changes to my IR phototransistor circuit.

DIY compass module

Hi A few days ago an idea in my mind to make a simple and cheap compass (module). I made a gradient ring in photoshop (see atachments). The idea is that i will stick this ring on a normal compass so that it rotates with the compass. After that an ir phototransistor will be fixed over this ring and will be mounted on the main compass frame which doesn' rotate with the compass. This phototransistor will be connected to a transistor or some other circuit (which i haven't thought of yet) which will amplify the phototransistor's voltage and send it to a picaxe's analog input pin.

Do task according to pulse count or frequency


I am trying to make a program for a picaxe 20m2 chip such that it continuously counts pulses in 100 milli seconds and do specific tasks according to the no. of pulses, for ex- light an LED connected on pin b.0 for 1 second when the pulse count is 100 and light another LED which is connected to pin b.1 when the pulse count is 200. it should be like that it ''continuously monitors'' the pulses coming on one of the pins (say c.7) and do tasks accordingly but I have no idea how to do it.

Using Nokia DKU-5 cable to program picaxe (Working now!)

Hi guys

I read this article- http://letsmakerobots.com/node/23728 by Ro-Bot-X and i bought the same nokia cable (CA-42) from a local computer shop. It looked like this from 'outside'.


But wait when i cut opened it it wasn't CA-42!. It was nokia DKU-5 cable based on PL2303,

Picaxe, Windows 7 and 'Serial port'

Hi everyone,

A few days ago, I tried to programm a picaxe microcontroller via the serial cable on my windows 7 PC but it gave an error like 'no hardware found on comm port4 ' or the same with 'comm port3' etc.. when I changed the serial port settings in programming editor software. If you are facing the same problem then this may be the possible solution (well it worked in my case).