Simple, reliable communication method across 300 feet of Cat5?

uxorious

I am planning to replace a nursery paging system at a church with one that works functionally the same, but has additional communication features. The current one uses a 3 conductor cable (microphone cable to be exact). This carries 12 volts, ground, and a signal line. The current install requires a 260 foot long cable. The circuitry in the unit is potted so I can't determine the communication topology used. I am planning on using a simple Basic Stamp circuit with an LCD as a host unit that will communicate to a "receiver board". This receiver board will drive a 3 digit 12" tall LED display. The current unit I have looks similar to one from rptelectronics called the silent usher.

My question is this: What's the most reliable way to communicate from a basic stamp across a 300 foot long cable so that I don't have to worry about data corruption caused by signal timing issues? I plan on using Cat 5 cable, so I have 8 lines to work with as opposed to just 3.

thanks,
dRu

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~~ dRu ~~

Phil Pilgrim (PhiPi)

Can you provide power at both ends, or just one end? If the latter, which end?

-Phil

uxorious

Can be either end, but would prefer that the cable is the only connection so that a local power source for the display is not a variable.

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~~ dRu ~~

JonnyMac

Peter Montgomery -- an active participant in the SX forum -- has a computer-based animatronic control system that uses 68HC11/SX28 nodes with power and communications (RS-485) are all routed through CAT5 cable. See www.socalhalloween.com