Simple RF Transmit and Receive

[koossa]

Dave

In your code for the receiver there is a pin for the pulsout, GPIO.1.
Is this the CD Pin?

[dhouston]

If you continue to use SerOut with the transmitter, then the receiver RXD pin output timing will be the same as RS232 but the polarity will depend on what polarity you use at the transmitter. The COM port on a PC expects inverted polarity.

However, the RF link in the example code I'm suggesting is not RS232 compatible. It is an example of the NEC protocol which is widely used for remote control and for applications like yours. X-10 uses it for all of their RF applications, including motion sensors. For an RF link it's much simpler to implement than SerIn/SerOut and is very reliable for small amounts of data. It does use Debug to output the received codes to a PC serial port. See the PBP manual for how to implement this.

I think you mean GPIO.1 and PulsIn. That is equivalent to your RXD pin. The code was written for ASK modules which have no CD so you can ignore CD if you try to adapt my code.

[koossa]

Dave

I am busy implementing your code and all your suggestions.
What must the Comm. port settings be on the PC Side (see attachment)?
I'm using MS Terminal to monitor the incoming data on the PC.

[dhouston]

What must the Comm. port settings be on the PC Side (see attachment)?

9600 8N1 - See the Define statements in my example.

DEFINE DEBUG_REG GPIO
DEFINE DEBUG_BIT 2 				'GPIO.2
DEFINE DEBUG_MODE 1 				'Inverted
DEFINE DEBUG_BAUD 9600

You will need to change DEBUG_REG and DEBUG_BIT to reflect the pin you use for output to the PC. I wrote this for a 12F629.

[koossa]

Ok, so my settings is correct, but it does not work?
I will upload my new schematics and code.
Mayby I have missed something.

[koossa]

Dave

I have updated my Schematics and used your source code.
I have made a couple of mods on the code, but it does not seem to work, don't know if I have missed something.

I am using MS Terminal to view the incomming data on the PC. The data did only came through once and it was a couple of junk characters.

Thank you very much for all your help!!

[dhouston]

In your schematic, change both 22K resistors to 1K. These merely limit the current to what is safe. 5V / 1000R = 0.005A (5mA). The 22K is needed only when the voltage is higher as with an input from a PC using RS232 voltage levels. Here, all the voltages are 5V max.

In the code, comment out IF (space<40) OR (space>175) THEN init.

In the code, modify DEBUG (RF[i] REV 8) to send either hex or decimal representations of the bytes. I'll let you consult the manual for details. My code sends the Ascii byte values which may not all be printable characters, especially in MS Terminal.

HEX 50 AF 42 DB
DEC 80, 175, 66, 189
ASC P, », B, ╜

The protocol is explained at http://davehouston.net/rf.htm