Subject: From: Date:

Re: [ECS] Prairie Digital Dan Carrington Fri, 12 Feb 1999 08:50:16 -0800

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	Overall I prefer the Micro Redac, but it is more expensive and may not
even be available anymore.  The Prairie Digital Model 40 gives you 28
lines of individually selectable digital In or Out.  It gives you 8
analog inputs if you give up 4 Digital's for the information bandwidth. 
It lets you control up to 3 stepper motors by using some of the
Digital's but I don't remember if ECS lets you do this feature.  And it
only cost me $99.  
	Now for the downside.  It needs a $30 accessory kit for general use
(power supply, serial cable, and output ribbon cable).  The unit itself
only has a 50 pin ribbon cable connection for it's output.  I wanted
lots of relays so I had to build a relay board for the digital outputs. 
Not terribly expensive but still had to build the dang thing.  I used an
IC driver for powering the relay coils and drove the IC with the digital
outputs of the model 40.  The chips are 2003 Darlington arrays that bump
up the digital output power to drive the relay coils.  If you just want
to access the wires themselves for digital I/O, they sell a breakout
that brings the 50 pin ribbon to screw terminals.  Overall I have had to
tweak with the thing some.  The digital (relayed) outputs work fine.  I
use them to control a stereo that I can not find an IR that talks it's
frequency.  I jacked into the system and tapped onto the buttons.  The
model 40 also gives you an IRQ high/low trigger thing that I have never
figured out how to do anything with.  I do use one of the Digital I/O's
as an input and it works fine also.  As to the analog inputs, I have not
wired them to anything yet as I don't use many analogs and I still have
spares on my micro redac.  I have the model 40 on a UPS, but the few
times it has taken a really odd power hit, I have had ECS loose
communications with it and have had to reach back and power down and up
the model 40 to reset it.  I have never had that problem with the
micro-redac.  
	As my overall rating, I will buy another when I need more digital
inputs. (providing nothing better comes on the market at a comparable
price)  I will buy a breakout screw terminal board for that use.  I
don't want to make another relay board if I need more relays, but I
don't know of much else anywhere near the price that gives relay
outputs.

Dan Carrington




hutchins.ta@pg.com wrote:
> 
> Dan,
> 
> How much did it cost, and what are you using it for. I want to hook up a
> fair # of temp sensors (DS1820?) and also some other things ,relays,
> security ect. Will it work for that w/ ECS?
> 
> Tom

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