Re: UltraLite serial cable question

Brian Smithson (brian)
Sun, 19 Apr 92 20:52:59 PDT

> My question is this: Is this flush pin 1 normal on the cable? If no,
> where can I get a replacement serial cable? If yes, what does it take to
> print to a serial printer?

My cable has the same thing. Pin 1 is flush, pins 2,3,4,5,6,7,8,20, and 22
are normal, and the rest simply aren't there at all.

> Come on, people, all I ask is that you take a look at your serial cable
> and reply, please! Even a pinout of the serial cable would help.

The DB25<->DB9 adaptor which is supplied with the UltraLite is not wired the
same way as a standard PC/XT<->PC/AT serial adaptor. In addition to the DB9
end being female instead of male, the wiring is different. Here is the

DB9 DB25
--- ----
1 6
2 2
3 3
4 6
5 7
6 8,20
7 5
8 4
9 NC

[S=sheild, NC=no connection]

The UltraLite serial cable has the following wiring with and without the DB9
adaptor, referenced to the DIN connector:

DIN DB25 DB9 Function
--- ---- ---- --------
a 7 5 signal ground
b 8 6 carrier detect
c 20 6 DTR
d 3 3 receive data
e 4 8 RTS
f 5 7 CTS
g 6 1,4 DSR
h 22 NC ring indicator
i 2 2 transmit data
S S NC protective ground

[S=sheild, NC=no connection]

UltraLite DIN connector labels, as viewed from the pins:

a b c
d e f g
h i

Back to your original question, why can't you print serially?: I don't know
and I haven't tried. All of the correct signals seem to be available, but
there is something strange about the way the adaptor is wired. Perhaps
someone else has gotten it to work or has looked closely at NEC's wiring?

-Brian Smithson
 Motorola Inc., Computer Group, Commercial Systems Division
 10700 N. De Anza Boulevard, Cupertino, CA 95014 USA, (408)366-4104, {apple | pyramid}!motcsd!brian