McGuire_Ed@GRINNELL.MAILNET (03/18/86)
I'm writing a program to dial out from a VAX 8600 using a DMZ-32 connected to a RACAL-VADIC 3451 programmable modem. There is no clear guide in the I/O manual to the services required to control a line with full modem control signals. I have gotten as far as determining that I must turn off character- istic TT$M_MODEM in order to send dialing commands to the modem, because VMS will not transmit to a "modem" if it does not sense carrier. But when I complete my call and sense carrier manually, I want to turn TT$M_MODEM back on so that VMS will detect hangup. When I set TT$M_MODEM, VMS drops DTR, causing a disconnect. The documentation indicates that VMS will drop DTR if one SETS, then RESETS TT$M_MODEM. Do I have to manually sense carrier loss? Has anyone else done dialout control? Please reply to: McGuire_Ed%GRINNELL.MailNet@MULTICS.MIT.EDU
aven@UMDHEP.BITNET (03/19/86)
The cover of the DECUS catalog says something like 'Don't reinvent the wheel!' How true! For dailing out from a VAX, the best program I've yet come across is VAXNET, available on most of the DECUS symposium tapes. It's far easier to modify the autodialer code for your own particular modem with VAXNET than for the stupid DF03_DTE.MAR dial routine for 'SET HOST/DTE'. I doubt you will need to write your own dialout program once you get VAXNET, but if you do, the VAXNET sources are a good lesson in asynchronous port control in FORTRAN. Todd Aven Systems Engineering, Inc.