Help me pick my wireless module
G McMurry
Posts: 134
I have an application that uses a bi-directional RS-232 link. BS2 on both ends, both units transmitting and receiving at the same time.
One side is a remote control unit that sends serial commands continuously to control a large scale train. The remote also has several serial displays that read out the condition of various functions (again continuously) from the train engine.
The other side of the link is the Train itself. It receives signals from the remote control such as throttle, brakes, lights on, etc. At the same time it sends serial back to the Remote details such as oil pressure, RPM, MPH, air pressure, etc.
Right now I operate at 19.2K but the speed is easily changed. the BS2s are using Serin and Serout.
The electrical interface i am using uses MAX232 RS-232 converters and I run the signals over three conductors. Ground, Xmit and Receive.
I just want the best wireless module to put inbetween the two units.
It looks like I might have to have 4 modules to do my job. Two on either end (one for transmit and one for receive).
Is that the case?
I like the form factor of the Xbee units but do any of them have both Transmit and Receive that can be used at the same time?
Greg
One side is a remote control unit that sends serial commands continuously to control a large scale train. The remote also has several serial displays that read out the condition of various functions (again continuously) from the train engine.
The other side of the link is the Train itself. It receives signals from the remote control such as throttle, brakes, lights on, etc. At the same time it sends serial back to the Remote details such as oil pressure, RPM, MPH, air pressure, etc.
Right now I operate at 19.2K but the speed is easily changed. the BS2s are using Serin and Serout.
The electrical interface i am using uses MAX232 RS-232 converters and I run the signals over three conductors. Ground, Xmit and Receive.
I just want the best wireless module to put inbetween the two units.
It looks like I might have to have 4 modules to do my job. Two on either end (one for transmit and one for receive).
Is that the case?
I like the form factor of the Xbee units but do any of them have both Transmit and Receive that can be used at the same time?
Greg
Comments
The xBee modules are probably the easiest to use. Make sure to download and read Parallax's guide to the xBee modules.
You'll need a 3.3V to 5V adapter between an xBee module and the Stamp. You won't need the MAX232.
Given you are transfering from a fairly reliable medium to a totally unpredictable one (radio transmissions can be lost, garbled etc) then going for something like Xbee is going to be a wise decision as this handles most such issues transparently to your existing code.
However almost certainly will have to think about fail-safeing your code for when there is a break in communications (graceful/safe shutdown, sporadic retry).