cutting the cord on RS232

Community Projects
1

Project help.

I have a lcd display and keypad connected via RS232 to a controller. I would like to cut the cord on the RS232 data so that the lcd keypad and controller can be hand held.

I was looking at this product SparkFun Bluetooth Modem - BlueSMiRF Silver. My problem is that I don’t know if you can pair these together to create the RS232 pipe (master/slave style).

I see in the notes that it says DO NOT connect to a computer. Why is that? My setup would be pc board -to- com expansion board -to- controller board-to- display/keypad

I want to cut the cord between the expansion board and the controller board

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I see in the notes that it says DO NOT connect to a computer. Why is that?

What the product page actually says is this:

Do not attach this device directly to a serial port. You will need an RS232 to TTL converter circuit if you need to attach this to a computer.

It will work fine for your project, provided you also obtain the converter.

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Be careful though. Even if your keypad-controller communication is not at RS232 voltage levels, you may still need a converter. The RN42 runs at 3V, so you may still need to convert between 5V <->3V levels.

Besides that issue, the RN42 works pretty well in this application. I have a couple of projects where I use them for serial cable replacement (the bare RN42 module; not the spiffied up Sparkfun breakout) and it’s a breeze once they are configured properly.

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Lets assume that this is a windows embedded machine with a com expansion board. Manufacture has verified this com port is transmitting RS232 data. How would I be able to hook up these Bluetooth modules to create a RS232 pipe so that I can cut the cord. What do I need between the PC and this Bluetooth board to make it work.

Thanks in advance

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https://www.sparkfun.com/products/449

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All in one unit:

http://gridconnect.com/bluetooth-to-serial.html