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Re: Solving the need for ISA or USB slots and Serial Ports



Yes I meant TCP, sorry.

There is a serial port version of Uni_Trac in development that will work on
a 486 system - this should bring down the cost of tracking/tuning to a
reasonable level. This version will also allow the use of USB<->Serial
adapters.

73's

Don Woodward
KD4APP
AMSAT 33535
kd4app@amsat.org
http://kd4app.webhop.org


----- Original Message ----- 
From: "Bruce Bostwick" <lihan161051@earthlink.net>
To: <amsat-bb@AMSAT.Org>
Sent: Wednesday, July 02, 2003 15:16
Subject: Re: [amsat-bb] Solving the need for ISA or USB slots and Serial
Ports


Do you mean TCP?  IP isn't necessarily guaranteed for delivery either.
Although, you're right, either the node will need to be smart enough to
be able to prevent damage if the start command goes through and the
stop command doesn't.  Although, what I was thinking of for rotators
was more of a servo loop control, where the computer would send out a
specific "setpoint" value, fed to the rotor servo as voltage, current
loop, what have you, and the rotor would automatically track that
setpoint and not need separate "start" and "stop" commands, just a
single write and latch operation into a DAC.

I know most rotators today don't do it that way, but I've been thinking
for years that it's time they did .. simpler control and less chance of
runaway operation.  It's simple enough to do nowadays .. three wire
interface with DC power, ground, and setpoint voltage .. and you can
even limit the input voltage with simple op amp circuits so if a short
somewhere drives the input to one rail or the other the rotator will
still not end up grunting against the stop.

Yeah, I know, I'm being an armchair engineer, but it's worth thinking
about, since basically it's a gear reduction DC motor, a position
sensing pot, and some op amp circuitry with maybe a few MOSFET driver
bridges added in.  Definitely feasible in this day and age, and would
integrate very nicely with a LAN-based station control system ..

On Wednesday, Jul 2, 2003, at 13:59 US/Central, Don Woodward wrote:

> UDP is not guaranteed for delivery whereas IP is - do you really want
> your
> rotator to be commanded to be moved without ever receiving a "stop"
> command? Of course the limit switches would kick in but it could
> potentially over-use some of these rotators which are not designed for
> constant use.
>
> Or even worse a TX command to key your radio without a unkey?
>
> 73's
>
> Don Woodward
> KD4APP
> AMSAT 33535
> kd4app@amsat.org
> http://kd4app.webhop.org
>
>
> ----- Original Message -----
> From: "Bruce Bostwick" <lihan161051@earthlink.net>
> <snip>
>
> My vote goes with TCP/UDP over IP, hands down.  There are way too many
> out of band protocols running around on LAN's as it is, and not all
> switches or routers deal with those gracefully.  I have painful
>
> <snip>
>
>
Heard from a flight instructor:
"The only dumb question is the one you DID NOT ask, resulting in my
going out and having to identify your bits and pieces in the midst of
torn and twisted metal."

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