to use /dev/tts/0 you must tell the kernel not to open a console at this device and you must have installed the setserial
Then login in your wrt -box and go to /etc
edit the file named inittab with vi , the interesting line in this file should look like this:
you have to change this line ( comment it out ) , after your change ist should look like this :
save the changed inittab
reboot your wrt
Well now you have disabled the console on /dev/tts/0 and you can use this device for other things
And be sure that you have installed the setserial package
There MUST be a startscript /etc/init/d/S15serial
in the file you should find this :
/usr/sbin/setserial /dev/tts/1 irq 3
This is very important , normally after boot the device /dev/tts/0 have the IRQ 0
if you have the setserial -package installed , the above script was aumatically installed and set the IRQ for
/dev/tts/0 to IRQ 3
Its not complicated to use this device you must only comment out 1 line as described above in the inittab -file and you must have installed the setserial package
And ... YES YOU HAVE NO SERIAL CONSOLE AFTER THIS MODIFICATION ...
This is , that only 1 process can use /dev/tts/0 .
AND AGAIN YES , YOU CAN SEE THE BOOT -MESSAGES DURING THE BOOT at 115200 baud ,8N1 .
This works for me here at a WRT54GS wit the lastest Experimental Version .