ttl@sti.fi (Timo Lehtinen) (07/23/90)
The dc(4) man page (in ULTRIX V3.1D) says that the serial line controller on DECstation 3100 and 2100 only provide partial modem control. Could anyone enlighten me as to what functionality specifically is missing ? I'm writing a program which needs to sense whether Carrier Detect is on and can't figure out how to do it. For instance ioctl(fd, TIOCWONLINE); /* wait for carrier */ never blocks regardless of whether I have a cable on the port or not. Is it me or the dc0 ? Any help much appreciated, Timo -- Timo Lehtinen Internet: ttl@sti.fi Stream Technologies Inc. X.400: C=fi,A=fumail,P=inet,O=sti Kivihaantie 8 C 25 Phone: +358-0-573161 SF-00310 HELSINKI +358-49-424012
obg@sics.se (Olof Backing) (07/23/90)
ttl@sti.fi (Timo Lehtinen) writes: >The dc(4) man page (in ULTRIX V3.1D) says that the serial line controller >on DECstation 3100 and 2100 only provide partial modem control. Could >anyone enlighten me as to what functionality specifically is missing ? >I'm writing a program which needs to sense whether Carrier Detect is on >and can't figure out how to do it. For instance > ioctl(fd, TIOCWONLINE); /* wait for carrier */ >never blocks regardless of whether I have a cable on the port or not. >Is it me or the dc0 ? >Any help much appreciated, From what I've heard from the DECpeople here in Sweden, the serialport on a DEC3100 (and I guess DEC2100) will only support the following: 1 - frame ground 2 - TxD 3 - RxD 6 - fuzzy comb. of DCD & DSR 7 - signal ground 8 - see pin 6 20 - outgoing DTR But thats only valid for one of the serialports. Cant remember which one at the moment, but do a 'file /dev/tty0[01]' and you'll see. WHOAMI: Olof Backing EMAIL: WHERE: Swedish Institute of Computer Science (SICS) obg@sics.se SNAIL: Professorsslingan 25/102, S-104 05 Stockholm, Sweden VOICE: + 46 8 166318