admin@cs.exeter.ac.uk (System Administrator) (01/24/91)
[ I am sorry if you have seen a similar article - the previous posting had the wrong address so I have sent a cancel message and reposted this ] We are experiencing some problems with the apollo (domain OS 10.2 bsd) serial port whilst attempting to drive a postscript laser printer. As far as we can determine the problem occurs when the postscript file has finished its job and the printer sends a Ctrl-d back to the computer. At this point the computer echos two backspace's which the printer sees as errorneous postscript, ignores further input, timeouts, sends end of job (ctrl-d) to which the computer sends 2 backspace's and the cycle continues. We have played about with the port settings and have echo off and even have ctlecho off but cannot convince the serial port not to echo the two backspace's. We believe at this point that there is a bug in serial driver in that there seems to be no way to turn this echoing off. According to our understanding if the "stty ctlecho" is set then when we do a Ctrl-d the terminal driver quite correctly first displays ^D and then immediatly sends 2 backspace's and spaces before terminating the shell (or subshell). If on the other hand the "stty -ctlecho" is set then on sending a ^D the shell correclty does not put it on screen so there is no need to send the two backspace's but the terminal driver still does. Has anyone met with similar problem or better still can anyone suggest a soluton or see where we are going wrong. -- Khalid Sattar JANET : admin@uk.ac.exeter.cs Computer Science Dept. UUCP : admin@expya.uucp University of Exeter BITNET : admin%uk.ac.exeter.cs@ukacrl Exeter, UK. Tel : +44 392 264062 -- Khalid Sattar JANET : admin@uk.ac.exeter.cs Computer Science Dept. UUCP : admin@expya.uucp University of Exeter BITNET : admin%uk.ac.exeter.cs@ukacrl Exeter, UK. Tel : +44 392 264062
wjw@ebr.eb.ele.tue.nl (Willem Jan Withagen) (01/25/91)
In article <ADMIN.91Jan23165838@exsg.cs.exeter.ac.uk> admin@cs.exeter.ac.uk (System Administrator) writes: >[ I am sorry if you have seen a similar article - the previous posting >had the wrong address so I have sent a cancel message and reposted >this ] > >We are experiencing some problems with the apollo (domain OS 10.2 bsd) >serial port whilst attempting to drive a postscript laser printer. [deleted stuff about ^d] >We believe at this point that there is a bug in serial driver in that >there seems to be no way to turn this echoing off. > >According to our understanding if the "stty ctlecho" is set then when >we do a Ctrl-d the terminal driver quite correctly first displays ^D >and then immediatly sends 2 backspace's and spaces before terminating >the shell (or subshell). If on the other hand the "stty -ctlecho" is >set then on sending a ^D the shell correclty does not put it on screen >so there is no need to send the two backspace's but the terminal >driver still does. Well there's always the diffence between using stty and /com/tctl. You can get the system as far as raw with stty and then you ask for the tctl settings and there still not raw :{. Furthermore is the still a bug in the SR10.2 serial driver. I was able to generate a rather small file which will print eronously on a serial port on an SR10.2 system. My support rep tells me that it is fixed in SR10.3, so there is further fix to the serial driver for sr10.2. [ this is already after installation of the patch for the sio-driver ] Ciao, Willem jan Withagen Eindhoven University of Technology DomainName: wjw@eb.ele.tue.nl Digital Systems Group, Room EH 10.10 BITNET: ELEBWJ@HEITUE5.BITNET P.O. 513 Tel: +31-40-473401 5600 MB Eindhoven The Netherlands