View Full Version : Which MCU to be use Please HELP me..........

01-14-2009, 02:35 PM
I am a begner and don't konw which micro controler to be used for a 4 whel robot which is controled by a remote.
It should move forwad,Reverse and Right Left
so which Microcontroler should I use ?
what would be the program ?

Thanks You

Yogesh Patel

01-14-2009, 05:41 PM
Choice of controller is no big issue. U can start with a philips P89V51RD2 which can be easily 'flashed' using it's free uploader.

However u will have to look out for a cheap /cost effective IDE to program this controller. Keil microvision 2 (or 3) is most widely used for this purpose (it's eval version limits u to a code size of 4Kbytes when programming in C language, which may be sufficient for you)

For controlling the 'wheels' are u planning to use DC motors or Stepper. DC motors are cheaper but to control them, u'll have to use a PWM to regulate the voltage to it. the P89V51RD2 has on chip PWM generators (on PORT 1, if i'm not mistaken). H-bridges or ULN2003, are use to interface between the controller and the motor.

For wireless transmission, u will have to search an appropriate transceiver (IR or RF) with an onchip PLL (U get alot of these in the market) or for a short distance you can use an IR transmitter - Receiver LED pair. This can be connected to the TXD & RXD pins of the controller.

As far as the program is concerned, it should continously listen to the input from ur remote (via the wireless), and on reception of a valid message, it should start a PWM to the motors (OR vary the PWM to have a change in motion.)

If Ur planning to have the 2 front wheels to control the direction of the motion, then an appropriate motor and mechanical setting should be done in order to achieve this. For me the best way would be to use 3 wheels, keep the front one as a free moving wheel and connect 2 seperate motors to the behind wheels. In normal motion, both the motors move in the same direction and when a turn is required, they will have opposite directions. You can even vary the speed of each motor in the same direction to have a gradual turn.

01-14-2009, 05:47 PM
one more thing, u can go to this site


01-14-2009, 07:36 PM
THanks a lot
But If I don't use wireless remote control then what will be the changes..?

Actually I want to first build simple robot and then I will go on making changes and more Improvements ... what do you say ?

01-14-2009, 08:22 PM
there is a article on this site for this topic. you can refer it. its in the Topics section.

my advice.... lookout for programmer first. see which programmer you can arrange. look in your college, with friends, seniors. then use the uC that programmer can burn. choose the lowest(cheapest) series in that uC. dont know about others but i fried 3 uC before getting the 4th one working.

if no programmer is available then you have to decide whether you want to build one or buy it.