When we are playing with arduino, it’s very interesting to add wireless comunications for a wide variety of appliactions such us R/C, WSN or Home Automation.

For me RF it’s a very charming field, maybe because I’m amateur radio since long time. So I love to play with arduino connected to radio data transceivers.

I found APC-200A-43 with a different name (CM12111) from an ebay seller. These data transceivers looks great because their flexible characteristics:

  • Outdoor line-of-sight range up to 200meters(9600bps)
  • Frequency range 431-470MHz
  • 0.2MHz channel spacing
  • Output power:20mW(adjustable)
  • One interface of TTL,RS232,RS485
  • Selectable baud rate data in RF
  • Selectable baud rate data in serial comunications
  • Outstanding receiver sensitivity -113dBm@9600bps
  • High efficiency forward error correction with interleaving encoding
  • GFSK modulation
  • Main parameters can be changed by APPCON RF module software
  • 256Bytes data buffer
  • External SMA antenna connector
  • Power supply with voltage +3.3-5.5V
  • Power consumption:RX current:28mA,Tx current :40mA
  • Operating temperature:-30℃to85℃
  • Size:39*19*7.0(mm)

 I checked the coverage for that devices with the following conditions:

  • Using external antenna for both portable transmitter and static receiver
  • beacon positions sent every 15 seconds
  • RF baud rate transmission: 1200bds
  • Walking in city

As result back at home I was able to draw data over a map and the limit distance in that conditions were about 650 mt.

BUT….. the usual problem of this RF modules is not the coverage but the difficult to get the configuration running. Maybe you reach this blog looking for a solution to that problem.

Let’s talk about that configuration program. The program is RF-Magic V4.2, quite easy to use, but normally the problem is achieve the communication between module and PC. The problem I found when I was trying to proceed was… There’s no way to link with the program if you’re using a USB FTDI Converter!

So, the following steps shows how to get a positive result linking program and modules.

  •  Use a RS-232 to TTL converter (MAX-232).
  • Check that the COM serial port is the lowest possible COM (never use COM15, for instance!!)
  • Connect the Serial converter and the RF module to the available port. Some people said that the converter has to be connected first and the RF module must be powered after software is running. I tried to do it at the same time and there’s no problem, maybe because I’m using parasitic power supply from COM port.
  • Run RF-Magic V4.2 Software
  • The status bar should look like the following figure

  • Read, Write, and perform all changes you want!

That should be enough.