Hi MindBender,
Thanks for your reply and sorry for my strange english :)
No, my catgenie work well with B04 and serial connection. A lot of time ago a made my software with a small modification, in fact I has only modify the time to start the cleaning program after 30min that the cat has used it. I used the old MPlab + Hi-tech C pro to make it.
Until now the catgenie work well with the firmware B04 and the serial connection.
Unfortunately when the light guide is dirty, some time appens that the bowl turn forever with full water inside. In this case the serial connection is more pratical to turn on the drain pump.
I know that the new B05 has the security check if the light guide is dirty, but for me, the serial connection it is indispensable in case of problems.