Why is my ComPort not accepting the data, I am writing?

maheshnimje · 04-27-2006, 02:12 AM

Hello all,
I am able to contineously fetch(read) the data from com Port, but I am not able to write the data to the comPort. Can you all help me with the same. My work is suspended. Please reply me with the small lines of code so that I can proceed forward.

With regards
Mahesh N. Nimje

DaveG · 04-28-2006, 11:11 AM

Device ownership and permissions? ls -l /dev/ttyS*

To allow ANYONE to write to the serial ports (as root):
chmod 666 /dev/ttyS*

Alternatively, check the group ownership and permission. If it's something like "uucp" then add the uucp group to your list of allowed groups.
As root,
usermod -G <current groups>,uucp <your user id>

Also check if udev manages the devices. You may need to update the udev rules to make any changes permanent.

maheshnimje · 05-08-2006, 11:38 PM

My comport is working fine. I was not able to write on a comport. Now I am able to because, the format they gave for our device to interact with the device is in the Hex format. If we are transferring the data in hex, it is giving the ack for the same.
Thanking you.....