[Rack] [Noisebridge-discuss] minotaur is down

Jake jake at spaz.org
Fri Jul 5 23:31:57 UTC 2013

what's wrong with the rs232 we're using now?  inside each keypad is an 
atmega328 connected to a MAX232 chip, which translates the TTL serial of 
the arduino the real +-12v RS232 for the long haul.  Also it's 300 baud.

we don't need rs422 (whatever that is) for long runs of wire because we 
have ethernet, and wireless (thanks to you)

a nice thing about RS232 is that the computer at the end of it already has 
the transciever built in.

if you want to play with obscure data transmission stuff, find me a router 
or two with DS3 ports, so we can use these QAM16 modulators to beam stuff 


On Fri, 5 Jul 2013, Adrian Chadd wrote:

> On 5 July 2013 16:18, Jake <jake at spaz.org> wrote:
>> well, the payphone is one physical serial port, and the upstairs keypad is
>> another.  These are important because they are actual RS232 lines running
>> long distances (like in the 1970's) and they are pretty mission-critical
>> (literally in the mission) and the extra USB-serial layer would suck for
>> that.  so i'm glad we don't need to do that.
> rs232 over long distance? why not just whack up RS422 and an Arduino?
> I wonder if I should acquire some rs422/rs485 stuff and build some
> long distance (100s to a couple thousand feet) long bus topology of
> arduinos. Would there be any interest in a talk/demo of that kind of
> stuff?
> Adrian
> (Yeah, i did a stint in control systems.)

More information about the Rack mailing list