hann@rd1632.Dayton.NCR.COM (Ed Hann) (03/08/90)
I just finished configuring a Tower to use a PostScript printer on a serial port, and discovered a strange situation. The Tower is a Tower 32/600 with Tower OS 3.00.01. The PostScript printer is an NCR 6416 laser printer with the contoller replaced with a PSJet+ controller. This makes it equivalent to a QMS 800+ laser printer. The printer is configured to use the 25 pin channel: 9600 baud, parity ignored, DTR protocol. I used a cable wired like a 1308-C037/C036 Intelligent Terminal Cable, as described in NCR TOWER Series Site Preparation Guide, page B-13, which says this will work with an NCR 6416 Laser Printer. I experimented with different parameters for the gettydef entry in /etc/gettydefs that is combined with the a model /usr/spool/lp/model/laser to create the printer interface file /usr/spool/lp/interface/printer2. I finally got the following getty definition to work: laser# B9600 CLOCAL CS8 ICANNON # b9600 CLOCAL CS8 ICANNON # # laser ^^ Please note the misspelling ||. I inadvertantly mistyped the parameter. The documentation spells it ICANON. Other entries in gettyfefs also spell it ICANON; yet it works. I didn't discover this until I was configuring an identical printer with an identically wired cable on a Tower 32/600 with Tower OS 1.03.02. I used the proper spelling in /usr/spool/lp/local/lpgettydefs/laser (the gettydef file is located in a different place in 1.03.02). I used the same model as that used on the previous Tower. Everything appeared the same, but the printer would only flash briefly, and no print would come out. I concluded that since I had misspelled ICANON on the other Tower, the parameter was not needed. Without the parameter I got the same symptoms, so I added it back, but used the incorrect spelling ICANNON; and it now works. WHY? Is the documentation wrong? Is ICANNON actually right? Does something good happen with misspelled parameters? The following code is a copy of the model I used on both Towers: ########################### Model begins here ############################### # lp interface for psjet+ laser printer # copies=$4 shift; shift; shift; shift; shift files="$*" i=1 while [ $i -le $copies ] do for file in $files do echo "\004\c" cat "$file" 2>>/tmp/laser$$ echo "\004\c" done i=`expr $i + 1` done mail lp </tmp/laser$$ rm -f /tmp/laser$$ exit 0 ########################### Model ends here ############################### The following represents the wiring diagram for the cables: DB-15 Tower DB-25 Printer |--- (Connect to Shield) | |--- 1 Frame Ground Transmit Data 1 -------------------- 3 Receive Data Receive Data 9 --------------------- 2 Transmit Data Request to Send 2 --------------------- 5 Clear to Send Clear to Send 10 --------------------- 20 Data Term. Ready Data Term. Ready 4 -----------------|--- 6 Data Set Ready | Data Set Ready 3 ---| |--- 8 Carrier Detect | Carrier Detect 12 ---|----------------- 4 Request To Send Signal Ground 11 --------------------- 7 Signal Ground -- Ed Hann (Ed.Hann@Dayton.NCR.COM) Applied Research, R&D Division (1 513 445-1061) NCR Corporation 1700 Patterson Blvd., Dayton Ohio 45479