[net.micro.trs-80] HELP! -- Printer Switch

lsl@ecsvax.UUCP (Elizabeth J. Laney) (10/08/86)

We recently bought a Radio Shack TRS-80 Printer Interface Selector for use with
our IBM-PC equipment.  We have found that use of this printer switch inserts an
extra line feed with each carriage return (ASCII 013) -- so that double-strikes
are printed on two lines and single-spaced text is printed double-spaced.

It appears that there is not a one-to-one correspondence between the connection
pins for input and output on the printer switch (although I'm not knowledgeable
enough to be sure).  Another confounding factor is that the plug for computer
input is for the round-type parallel cable shaped like this: 

                               __________________
                               \                /
                                \______________/

 
while the printer out plug is for the flat-type cable and shaped like this:

                               _________________
                               | ::::::::::::: |
                               -----------------


Another thing we've just discovered is that the switch works just fine (no 
extra line feeds) with the PC-XT, but will consistently give us the extra line 
feed with the regular IBM-PC linked to the IBM Graphics printer.  When the 
regular IBM-PC is linked to an Itoh Prowriter printer, however, again there is 
no extra line feed.
 
Any suggestions on how we can get the Radio Shack TRS-80 Printer Interface 
Selector to work in conjunction with the regular IBM-PC and the IBM-PC Graphics
printer?
 
Thanks,

Paul Williford
Student Micro Lab Coordinator
UNC School of Library Science
100 Manning Hall 026A
University of North Carolina
Chapel Hill, NC  27514
 
919-962-8188
 
lsl@ecsvax.bitnet