[GreenKeys] Model 28

[Radio AI2Q]

The way my computer talks to my Model 28 is via an old Kantronics UTU 
Universal Terminal Unit.  Check out the details on my Web page.

Vy 73, AI2Q, Alex
http://ai2q.org/


NNNN



----- Original Message ----- 
From: "tony.podrasky" <tony.podrasky at gmail.com>
To: "Brad" <unclefalter at yahoo.ca>; <greenkeys at mailman.qth.net>
Sent: Wednesday, October 21, 2015 3:44 PM
Subject: Re: [GreenKeys] Model 28


Hello Brad;

There was no link provided - so I can't see what kind of machine it is.

There are A REAL LOT of obstacles in getting the 28 to talk with a computer:

1. The 28 is a 5-level machine (uses 5 bits to communicate) The computer
    uses a 33 Teletype machine which is 8-level (uses 8 bits to
communicate). The 28 has a 32 possible characters. the 33 has 256.

2. The 28 runs at 45.45 BAUD where as the 33 runs at 110 BAUD. You would
    need to write a program to convert the speeds.

3. The computer may have a RS-232 EIA interface where as the 28 has a 60ma
current loop.

4. If your computer doesn't care about upper/lower case characters
(in other words, it sees an "A" the same as it sees an "a", you'll
be further ahead). My Linux box CARES about the case - so I had to
put "hooks" into my keyboard routine to tell the computer when I
was switching cases with my 35-KSR.

I got it to work, and it was worth every second I put into getting it
to work (I was after the CHALLENGE and not the RESULTS) but it was
pretty useless from a practicality standpoint.

UE,
K2EAA - TONY
NNNN
ZCZC