Hi all,
My arduino is programmed to respond to specific commands through serial port, but only when I insert the sd card it doesn't work, even that I didn't change anything from the code.
The sd card is automatically taking up all the serial port to itself. Is there a way to put the sd on and off from the serial port to be available?
Thank you.
obs: I'm sorry to post so many doubts in this forum 
even that I didn't change anything from the code.
What code? Which SD shield?
The sd card is automatically taking up all the serial port to itself.
It most certainly is not. The SD shield knows nothing about the serial port on the Arduino. The card in the SD reader on the shield knows even less about it.
Thank's and I can't understand why is working now...I tried it so many times! I'm using ethernet shield.
I want to know something else...
I'm using this ethernet shield + uno to use it like a webserver and the code is running from the microcontroller's memory (not from files that are inside the sd, like there are many examples on web). I want to use the sd only to log some data.
I don't know if there is something wrong with my pc/arduino, but it doesn't work too! I tested it many times and at this moment...
You have some code that you haven't shared.
It does something that you haven't shared.
You expect it to do something that you haven't shared.
And, yet, you want us to explain why what it does is not what you expect. Hmmm.