Subject: Re: Q: fake Terminal with MMJ plug alone?
To: None <port-vax@netbsd.org>
From: John <john@sixgirls.org>
List: port-vax
Date: 06/06/2001 18:20:19
> The subject says it. I want to put my MV3100 into an ISP rack as a
> webserver. The drawback is that normally there must be a terminal
> connected, or the machine won't boot. Later, the terminal can be
> unplugged without problem (but not switched off -> instant crash).
>
> As I understand, the terminal has some kind of "I'm here" signal.
> Can this be faked by soldering some wires of an MMJ plug together,
> or can it otherwise be faked?

Handshaking lines. You can connect the handshaking so that the machine
thinks it can send:

---------------
I             I  1 - DTR (Data terminal ready)
I 1 2 3 4 5 6 I  2 - TxD (Transmit data)
I             I  3 - GND (Signal ground)
I             I  4 - RxC (Receive common)
---------I    I  5 - RxD (Receive data)
         ------  6 - DSR (Data set ready)

Connect DTR (1) to DSR (6), and it should work.

John