[lcd4linux] serdisplib fails opening an usb display without error message

[Marcel <ta...@gm...>]

Hello!

I can't get lcd4linux open my usb display. Just compiled the svn source with 
serdisplib support (which is also handmade with libusb-support...), but 
lcd4linux just produces this:

marcel@d-wwow:~/Desktop/lcd4linux$  
sudo ./lcd4linux -Fvv -f /home/marcel/lcd4tanu.conf
Version 0.10.2-SVN-796 starting
[KVV] Using station 89
[KVV] Using default port 80
[KVV] Using default refresh interval of 60 seconds
[KVV] Default abbreviation setting: off
lcd4linux.c: initializing driver serdisplib
serdisplib: $Rev: 840 $
serdisplib: header  version 1.97
serdisplib: library version 1.97
serdisplib: open(07c0:1501) failed:

The usb device id is definitely correct:
marcel@d-wwow:~/Desktop/lcd4linux$ sudo lsusb
Bus 004 Device 003: ID 07c0:1501 Code Mercenaries Hard- und Software GmbH  
IO-Warrior 24
<snip>

I've also tried the X11 driver for testing which was successful, so there must 
be something wrong with serdisplib I think. But where may I start?

-Marcel