>This is a problem on the uProc side
>beacuse the system outputs regulary data on the RS-232, and if this
>output comes before the modem is finished seting up (Online indicator lights)
>the modem will hang up.

This appears to be a common problem with Hayes compatible modems. I had occasion
to get involved with trying to connect a modem to autoanswer when connected to a
machine which was trying to poll terminals continuously. The polling from the
host machine stopped the modem from answering the dial up call. The solution was
to make a little adapter box to go between the modem and controller, consisting
f a 1489 RS232 receiver, a 1488 RS232 transmitter, and a 78L05 to supply the
1489. The host controller had +/-12V available, and between the two chips, there
were enough gates available to gate the transmit line off until the carrier
detect from the modem went true. It all got built into one of those gadget
adapter boxes with db25 plugs on each side.