'96 Handbook CAT Interface Fix for FT-900

[Gene Eighmy]

I recently posted a question about using the computer interface found in
the '96 ARRL Handbook.  I was having problems reading status back from the
FT900 but I could write commands to it without any problem.  The following
from K8YSE fixed the problem and may be useful to others on the list:


>        Gene,

>        I had a problem with the interface that I built for my FT1000
similar to what you
>        are experiencing.  I can't remember which direction had the
problem but whichever
>        direction it was, the "0" level was not low enough.  And so the
interface decoded
>        a continuous "1"  The solution was to put a resistor from the
lead to ground.  Maybe
>        it was a 4.7k or so. This pulled the level down a bit and then
the port was able
>        to decode.  

>        When you send the command to query the radio for its status, does
the cat light come
>        on as if it is sending data back to you?  If it is coming on when
you command the
>        radio but not coming on when the data should be coming back,
there is another problem.
>        But if the light comes on and you don't get any data back, the
interface or your serial
>        port is not happy with the data.

>       John Papay  k8yse@en.com
>       http://www.en.com/users/k8yse

VE3KDH also gave me some tips about programming the interface:
>The update command (80h I think, with 2 I think as data gets current
status
>... and works, returns 16 bytes.

>I cannot get any of the other commands that return info to work.
(ie:opcodes
>that stat with F, like DIM, etc).  All others that that control only with
no data back work OK.

Thanks to all who helped.  I hope this will help someone building  the
Handbook IF.  Now I can get started writing code...

73,


-- 
Gene Eighmy - WD4MPS
Birmingham, AL
wd4mps@scott.net
eighmy@oxmoor.com