Interface to a Coyote Datacom 915XL radio modem

Tchman52

I have two Coyote Datacom 915XL radio modems and I'm trying to communicate with a basic stamp 2 wireless/serial interface. Has anybody ever tried this?

stamptrol

Haven't used the Coyote's in particular, but if they have serial connections in the 4800 to 9600 baud range they should work fine with the Stamps. What have you tried so far?

Note that you will be able to transfer data but probably won't be able to program the Stamp over the radio link.

Cheers,

Tchman52

My application for this is to recieve an alarm from a remote repeater building when there's a power loss. the distance is about 6 miles.

stamptrol

Had a quick look at the spec sheets. The radios have a serial interface so you'll have a Stamp at the remote end to detect the alarm and send the information to the radio. At the receiving end, another Stamp will receive the data and do whatever has to be done with it.

The radios are only 200mW so 10 miles line of site is probably under REALLY optimal conditions. Theres probably an application note on the manufacturer's website to help see what effect different antennas, coax runs and connectors will do to your expected radiated power.

Cheers,

Tchman52

Do I have to use null modem adapters on the radios? I found a website that has a similar application that works with basic stamp 2.
www.electrowave.com

stamptrol

By far the best way to answer the question is to look at the pinout diagram for the two devices and ensure Tx on the radio goes to Rx on the Stamp. And, vice versa. In a simple application like this one, try one connection and if necessary, interchange pins 2 and 3.
While there is a convention in the rs-232 standard as far as pinouts in different applications, manufacturers use different pinouts for various reasons.

Cheers,