serial connection (UART)

[Todespreis]

Hey there! I'm trying to implement a RTC to my GP2X. I wrote a script for my arduiino, i have an rtc module, it works fine. But i can't estable a serial connection from the arduino to GP2X. From PC is everything fine - i can login via puTTY and have access to the complete device. Here is a picture of it:

Post automatically merged: Nov 25, 2024

At the Line 14 from the bottom you can see the message, that the GP2X is starting a connection through /dev/ttyS0/. Is it a file on GP2X or is it the the one from my PC? Because, if i check the the directory on the handheld, i get this:

 

[Todespreis]

and i don't get the messages after echo - it says, /dev/ttyS0/ is a directory, but when i'm trying to access it, it says, it is not a directory. What? Why??? And why does screen not work? I'm already root on the device, what else should i do there?

 

[Linux-SWAT]

There is no "/dev/ttyS0/", I guess that the message should be read as "can't echo to a directory" (which is not possible).
So use /dev/ttyS0 instead.
To anticipate, it would be useful to check permissions with "ls -l /dev/ttyS0" or "ls -l /dev/tty*".

 

[Todespreis]

Thank you for the fast reply @Linux-SWAT I looked yesterday like for an half an hour on your post and thought - what the hell does he mean? X-D But i see now - it's the last forward slash. I think, i found something to try out in german forum:
https://pyra-handheld.com/boards/threads/gp2x-login-via-usb-gadget-serial.84604/#post-1472688
I think, the guy tries to implement there something, that works out of the box now? But at least i found a thread, where somebody says, that he got it working:
https://pyra-handheld.com/boards/threads/gp2x-serial-issues-hardware-gp2x-arduino.54291/