Re: ImageWriter<-IIGS cable

[dempson@actrix.gen.nz (David Empson)]

In article <2ns8dv$lsu@jadzia.csos.orst.edu>,
Yoshi <yoshi@CSOS.ORST.EDU> wrote:
> 	If possible, i'd like specs on how to build a ImageWriter to
> 	IIGS printer cable; even the pinout-conversion would be good.

Unless you're very good at making cables, it would probably be easier,
and give a better result, if you just went out and bought one.  The
same cable is used to connect a Macintosh to an ImageWriter.
Mini-Din-8 plugs are not easy to solder.

Having said that, here are the details you'll need.

You neglected to mention whether you are talking about an ImageWriter
I or ImageWriter II, so I'll cover both.

ImageWriter II first:

Each end of the cable is a male Mini-Din-8 plug.  The pinout of the
IIgs and ImageWriter II are identical (the ImageWriter doesn't use pin
7, "General Purpose Input").

Looking at the socket in the IIgs or ImageWriter II, the pins are
arranged as follows:

8 7 6
5 4 3
 2 1

The pin functions are as follows:

1  Handshake Out
2  Handshake In
3  Transmit Data Minus
4  Signal Ground
5  Receive Data Minus
6  Transmit Data Plus
7  General Purpose Input (DCD input), IIgs only
8  Receive Data Plus

The cable shield should be connected to the shield of both plugs - it
is Frame Ground.

The pin connections are basically swapped over:

1 to 2
2 to 1
3 to 5
4 to 4
5 to 3
6 to 8
8 to 6

Don't connect pin 7 at either end.  The resulting cable is symmetrical.


If you want to connect the IIgs to an ImageWriter I, the printer uses
a male DB-25 plug, and the cable pinout is as follows:

IIgs    ImageWriter I
1       6  (I think)  Handshake, computer to printer
2       20            Handshake, printer to computer
3       3             Data, computer to printer
4       7             Signal ground
5       2             Data, printer to computer
6 (no connection)
7 (no connection)
8 (connect to signal ground: pin 4 at the IIgs or pin 7 at the printer)

Connect the shielding of the two plugs together (preferably via the
cable shield), and to pin 1 (frame ground) at the printer end.

I'm not sure where IIgs pin 1 should go.  Pin 6 at the printer is the
most likely candidate (DSR, which is an input handshake line on the
printer).  CTS (pin 5) is another possibility.  In fact, you could
connect it to both pins to be on the safe side.  It is unlikely to be
needed, anyway.
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand