Problem with using PORT C in ATmega 32 for LCD interfacing

[royvincent]

I am using ATmega32 to display something in a 16x2 LCD screen.

The problem is, I have used PORT C for LCD connection and is not working. Later I erased the micro-controller and wrote a very basic program to alternatively make PORT C high and low with some delay (1 second) in between. Now, only 4 bits of PORT C is working as I expected. The rest 4 bits with some secondary function of JTAG is not giving proper output.

Is the JTAG fuse bits set?
But how?

Is there any way to bring them to normal mode?

Please reply...


Thanks

 

[nandhu015]

LCD interfacing

JTAG Enable fuse is located in High fuse bit. Bit 6

To disable write 1 to the fuse bit

Nandhu

 

[royvincent]

Re: LCD interfacing

I am using a serial device programmer named ponyprog.

Can you please explain me how to write 1 to that particular fuse bit?

Can it be done while writing the source code? I am using CodeVisionAVR. What is the command for it?


Thanks

 

[millwood]

LCD interfacing

Can you please explain me how to write 1 to that particular fuse bit?

is it possible that the device's datasheet has some information on that?

 

[royvincent]

Re: LCD interfacing

It seems I have solved my problem.

I used ponyprog and there is an easy to use fuse bit configuration interface where you just need to uncheck a box corresponding to JTAGEN.

Everything seems solved now.... Thanks


But, what is your opinion about Atmel shipping their micro-controllers with JTAG enabled by default?

 

[millwood]

LCD interfacing

it is always a bad practice to rely on the programmer settings to get your code to work. you should try to program the fuse in your code as much as you can so you know regardless of programmer settings, your code will always work in a way you expected it to.

 

[nandhu015]

Re: LCD interfacing

it is always a bad practice to rely on the programmer settings to get your code to work. you should try to program the fuse in your code as much as you can so you know regardless of programmer settings, your code will always work in a way you expected it to.

There is no possibility to program the fuse in code for avr controller

Nandhu