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From: res@cbnewsc.att.com (Rich Strebendt)
Newsgroups: comp.sys.tandy
Subject: Re: Help hooking Daisy Wheel Printer II to IBM pc
Summary: I have one hooked up ...
	    ... do something useful with yours ...
	       ... convert it to a boat anchor!
Message-ID: <1990Sep24.231949.4737@cbnewsc.att.com>
Date: 24 Sep 90 23:19:49 GMT
References: <6329@hub.ucsb.edu>
Distribution: usa
Organization: AT&T Bell Laboratories
Lines: 60

In article <6329@hub.ucsb.edu>, crmeyer@voodoo.ucsb.edu writes:
> In article <1990Sep21.155703.19465@chinet.chi.il.us>, les@chinet.chi.il.us (Leslie Mikesell) writes...
> >In article <2134@cipc1.Dayton.NCR.COM> rmackenz@cipc1.Dayton.NCR.COM (Robert Mackenzie) writes:
> >>At our church, we have a Daisy Wheel II printer connected to a TRS80 
> >>Model III.  Recently, we acquired an IBM compatible pc and we wish to
> >>use the printer on both systems.  Does anyone know how to hook the Daisy
> >>Wheel printer to the pc, or even if it is possible? 

I had a TRS-80 Model II on which my DW-II gave excellent service.  I
recently acquired an MS-DOS machine and hooked up the DW-II to it.

> >Physically, it should just require a parallel cable (the normal IBM PC
> >type).

That is correct.  I simply moved the cable from one machine to the
other and the printer was functional -- after a fashion.

> >However, you probably won't be able to use it directly from
> >DOS.  You will need to use programs that have a driver especially for
> >this printer or that allow you to build your own driver.  The problems
> >under MSDOS will be (a) the printer does both a carriage return and
> >linefeed when it receives a linefeed (if it's a IIb there should be a
> >control code you can send to control this), and (b) it doesn't understand
> >formfeeds. 

This is true.  I was able to write a simple filter program under UNIX
which did the appropriate new-line conversion to get rid of the CR+LF
problem.  I take care not to send formfeeds to it.

> Most, but not all, Radio Shack printers have a dipswitch or a jumper
> inside the printer to disable the auto line-feed function. Check the
> manual.

I looked into that when I first attempted to hook the two together.
The DW-II is much to primitive to have that level of sophistication.

A far worse problem, however, is the incompatibility in the handshake
between the printer and the MS-DOS or UNIX machines.  There is a lead
in the cable that the IBM/UNIX world interprets as a "wait a while, my
buffer is full" signal, but Tandy uses as a "I got your last
character" signal.  Upon receiving a character the DW-II printer
raises that signal and waits for the next character to arrive (in case
it is able to optimize the resulting carriage movements).  The
non-Tandy machine sees the signal and waits until it is removed by the
printer.  After about 100milliseconds the printer decides to go ahead
and print the character, then drops the signal.  The other machine now
send the next character and the whole game starts over.  The result is
that the printer is sloooooooowed way down to 10 char/sec. instead of
the appreciably higher speed (43ch/sec?) that it runs on a Tandy
machine.  It is really painful listening to the printer
putt-putt-putting along instead of ripping out lines of text as a
printer should.

I would recommend that the next thing you do with your DW-II is fill
it with concrete, add an eye=bolt to the top, and use it as a boat
anchor.

					Rich Strebendt
					...!att!ihlpb!res
					r.strebendt@att.com