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Mach
02-13-2009, 07:21 PM
http://img228.imageshack.us/img228/5899/atmega16myckqm6.jpg




I have designed the circuit by refering few sites
I would like to know wheter it is rite or wrong
any changes need to be made...
If any then please let me know

The purpose is that It will drive 4 motor of a robot.....
The IC used is ATmega 16
and a motor driver......

Please help me out....

pratikmahale
02-13-2009, 08:25 PM
If you need to control speed of motors then connect enable pins of L293D IC to PWM out put of ATMEGA 16 (OC1A & OC1B)

avinash_g
02-13-2009, 10:46 PM
Hello,

See
http://extremeelectronics.co.in/avr-tutorials/dc-motor-control/

And reletaed articles.

There's every thing about AVR MCUs

avinash_g
02-13-2009, 10:53 PM
TWO MISTAKES THERE !!!

The RESET line is floating when you remove ISP programmer the AVR chip won't function.

Use a 4.7k resister frm RESET to VCC

Why have u connected Aref to PIN2 of ISP (ISCP is for PIC MCUs)

One more mistake the Vs of l293d is different from logical supply Vss(Vcc)

refer to schematic given
http://www.extremeelectronics.co.in/avrtutorials/images/motor-controller.gif

Also provide pwr in Analog Supply i.e. the AVCC and AGND

Mach
02-14-2009, 03:13 PM
Also provide pwr in Analog Supply i.e. the AVCC and AGND

I have not understood this

can u explain me in detail Please.....


Thanks a lot......

avinash_g
02-14-2009, 05:07 PM
Hello,

Connect AVcc to +5v
and AGND to GND.

Actually these pins are connected to analog parts (ADC) and supply power to them.
These are kept separate fro digital supply that powers the digital part of the MCU(like the CPU).

For better analog accuracy and to reduce noise Atmel recommends a RL filter at the AVcc PIN. But as you are not at all using the ADC you can connect AVCC directly to VCC=5v.

Refer to data sheet for more info.

:D

Mach
02-14-2009, 05:44 PM
ya thanks I got it
and any thing else to be connected
If I connect it to COMP1 port will it be programed or I have to use a other programer....?


Thanks a lot

avinash_g
02-14-2009, 06:11 PM
See
http://extremeelectronics.co.in/avr-tutorials/part-iii-making-programmer-and-target/

to make a programmer

or get a USB Programmer from here

http://shop.extremeelectronics.co.in/product_info.php?cPath=21&products_id=28
8)

Mach
02-14-2009, 07:10 PM
where should I connect the Aref pin or it's not required???

avinash_g
02-15-2009, 05:11 PM
Hello,

Aref is the reference voltage for ADC and it is used when you wanna use a custom voltage for ADC reference. So u do not need to connect it any where for this application. Even if you use ADC it is only required when u need a custom reference voltage (two standard reference voltage of 5v and 2.56 volt is also available internally)

So leave it unconnected.


:wink:

Mach
02-21-2009, 07:03 PM
Thanks any more changes need to be made
Any more sujestions....?

Sumit Sinha
01-14-2013, 10:22 PM
Can anyone Please help me how to make usb avr burner... and how to burn program using different software ...