gonzalez@vax.bbn.com (09/18/87)
For some reason, RTS remains asserted after I close the tty. I fopen the file, apply ioctl to it, getc for a while, restore the original ioctl state, fclose and exit. RTS was inactive before I ran the code, went active for the run of the program, and remained active after the program terminated. I've done this on three different ports, with consistent results. HUPCL is set in both the original (system-generated) and application ioctl blocks. Subsequent runs of the program show the entire ioctl block to be the same as before the first run. The device is opened for reading only (it originally has been coded for read and write). Any ideas? Oh, I just discovered that doing a ^C on "cat /dev/tty__" produces the same effect. The equipment on the other end is wired DCE, with HPSM lines 5, 6 and 8 (CTS, DSR and DCD) ganged to the DCE's DSR (line 6). The equipment's DSR is inactive at the time. Pulling the equipment end of the cable makes no difference. There are no loopback's on the Masscomp end. The only other lines in use are RD, TD, SigGnd, RTS (obviously) and DTR, which each do straight to the corresponding (same-numbered) pins on the other end of the cable. -Jim Gonzalez gonzalez@bbn.com BBN Labs, Inc. (acoustics, not communications) Cambridge, MA