Re: [avr-gcc-list] Glitch on GPIO

[Galen Seitz]

Jahagirdar Gopal-AGJ005 <address@hidden> wrote:

> Yes, first I am configuring the direction register and then writing data
> in to it.
> Will this be a problem?
> will it work, If we write data first and then configure the direction
> register?
> 

I think that is the problem.  The data register has an initial value of
0x00 after reset.  When you configure a GPIO as an output first, the
initial value of 0 gets driven on the pin.  The pin will continue to drive
a zero until the corresponding data register bit is written with a 1.
Switching the order should solve your problem.

galen