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codeseo
04-13-2010, 07:25 PM
Am in process of making a line follower bot.
I have bought following components:

-X board mini atemga 8 http://shop.extremeelectronics.co.in/product_info.php?cPath=23&products_id=36
-7 line sensor array http://robokits.co.in/shop/index.php?main_page=product_info&cPath=11&products_id=43
-2A Dual Motor driver module with PWM control http://robokits.co.in/shop/index.php?main_page=product_info&cPath=1&products_id=176

Am confused between the connections how to couple them together.Can anyone help me out

Regards
CodeSeo

lolman_returns
04-13-2010, 07:28 PM
I think extreme electronics already has a lot of tutorials to help you with interfacing those components.

codeseo
04-13-2010, 09:39 PM
Actually am having problem interfacing motor controller unit with the MCU.

Whats diff between VDD and VCC in the motor driver??

lolman_returns
04-13-2010, 10:40 PM
Actually am having problem interfacing motor controller unit with the MCU.

Whats diff between VDD and VCC in the motor driver??
In your case
Vcc is Logic voltage = 5v
Vdd is your motor power voltage = upto 24 V in most cases.

Usually,
Vcc is collecter voltage usually BJTs technology and Vdd is Drain voltage usually FET technology.

I am sure you were given some sort of datasheet or manual with the product.

codeseo
04-13-2010, 11:57 PM
Nothing came with it.That what i dont like about robokit no product documentation.

Anyways i following doubts:
1) where shud i connect the 7 sensor array on MCU ADC or any pins
2) Where shud i connect the motor controller pins
3) And what the meaning of TTL output.
4) Shud i supply power on both in VCC and VDD of the circuit..

Regards

rao
04-14-2010, 01:19 AM
1) connect 7 sensor array to ADC pin given on the Xboard.
2) motor controller pins can go to any pin it just needs digital 0 or 1 in case of fixed speed, for speed control you need to put them at PWM (please contact Extreme Electronics for further assistance)
3) TTL = Transistor to Transistor Logic, usually 0-5V
4)The motor driver is a basic L298 driver breakout.

yes you will provide motor voltage (upto 18V) at vdd gnd, at Vcc and corresponding gnd you will provide 5V (logic voltage)

Xboard is a custom designed board and we would suggest you contact Extreme Electronics for questions related to usage and integration as they would be the best source.

avinash_g
04-14-2010, 06:51 AM
motor control
http://extremeelectronics.co.in/avr-tutorials/dc-motor-control/

I think you must have bought xBoard Mini long back because its obsolete long back. And new version is out there.

Avr programming is fairly simple and can be learnt in few weeks. We provide extensive tutirials for AVR .

Your task is also very simple , read input from 5 sensors and control 2 dc motors. From progrqmmers point of view its only simple manupulation of few io out lines by input received from five io in lines. And basic digital io is learnt at very beginning phase. I don't think it wont take more than two day to learn all these if you follow the documents on cd and do some experients.
As you already have a working hardware.

Avinash gupta
Extreme electronics.

codeseo
04-14-2010, 09:36 AM
I have a 7 sensor array.Can all 7 sensors be used on Atmega8 are there sufficient ADC pins on atmega8

avinash_g
04-14-2010, 10:03 AM
I think you know nothing. Why you need ADC ??? In a basic line follower either the sensor sensing BLACK or WHITE color? They why need ADC ?

You can do it with ADC too but then It will be a BAD Engineering Practice. Simply Make a Potential divider using a IR Sensor and a 100K POT hook the output of Potential divider to GPIO Pin of MCU thats it

avinash_g
04-14-2010, 10:07 AM
If you see the Robokits Doc about the sensor array it clearly state that the output are TTL . So why will you wanna use ADC ??? the output of sensor is either 0v or Vcc (may be 5v).

You are not following the Vendors documents and troubling the RI peoples to read it for you. For example I have to look into Robokits Docs to post this !


Pin 3-9 are output pins. These pins provide active low outputs. This
means it will provide Ground to microcontroller pins when the sensor
is sensing light color.

Above is an extract from Robokits Docs

avinash_g
04-14-2010, 10:10 AM
I have a 7 sensor array.Can all 7 sensors be used on Atmega8 are there sufficient ADC pins on atmega8

Do we here are sitting to read the Datasheet of ATmega8 for you ???

Go open tha datasheet and see how many ADC or (Kitchen Sink) the ATmega8 has!