execute RFSniffer and codeSend in nodejs - c++

Question

Both tools are available over here: https://github.com/ninjablocks/433Utils/tree/master/RPi_utils
I really want a simple interface to manage my 433mhz devices. but i can't find a good one.
So I have worked all day now trying to make a wrapper for nodejs to the RCSwitch class. with 2 simple methods
- send[code]
- recieve[callback[code]]
I get this error when i try to make a new instance of the RCSwitch class.
node: symbol lookup error:
/root/nodemodule/example/build/Release/kaku.node:
undefined symbol: _ZN8RCSwitchC1Ev
It compiles perfectly with node-gyp but when I execute node it fails.
Now I use exec to execute sendCommand with the code. (UGLY I Know)
And I tried to make the RFSniffer work like this:
./RFSniffer > rfsniffer.log
.Then tail -f the rfsniffer.log
But RFSniffer wont give me any data.
So my question is can anybody help me to get RFsniffer working with tail -f
Or even beter can someone help me fix the c++ addon for nodejs:)
Here is the wrapper code:
#include "RCSwitch.h"
#include <node.h>
#include <v8.h>
using namespace v8;
Handle<Value> CodeSend(const Arguments& args) {
HandleScope scope;
int PIN = 0;
RCSwitch mySwitch = RCSwitch();
mySwitch.enableTransmit(PIN);
mySwitch.send(args[0]->IntegerValue(), 24);
return scope.Close(True());
}
Handle<Value> CodeRecieve(const Arguments& args) {
HandleScope scope;
// Entry check
if (args.Length() != 2) {
ThrowException(Exception::TypeError(String::New("Wrong number of arguments")));
return scope.Close(Undefined());
}
Local<String> name= args[0]->ToString();
Local<String> msg = name;
Local<Function> cb = Local<Function>::Cast(args[1]);
const unsigned argc = 1;
Local<Value> argv[argc] = { Local<Value>::New(msg) };
cb->Call(Context::GetCurrent()->Global(), argc, argv);
return scope.Close(Undefined());
}
extern "C" {
static void init(Handle<Object> target) {
if( wiringPiSetup() == -1 ) {
ThrowException( Exception::TypeError( String::New( "rcswitch: GPIO initialization failed" ) ) );
return;
}
NODE_SET_METHOD(target, "Send", CodeSend);
NODE_SET_METHOD(target, "Recieve", CodeRecieve);
}
NODE_MODULE(kaku, init);
}
nodejs code:
var addon = require('./build/Release/kaku');
console.log(addon.Send(1234));
addon.Recieve(1234, function (val) {
console.log(val);
});

Answer 1

I had the same problem than you and the reason why ./RFSniffer > rfsniffer.log doesn't work is that printf() function in RFSniffer code is not flushed.
Try with this source code :
/*
RF_Sniffer
Hacked from http://code.google.com/p/rc-switch/
by #justy to provide a handy RF code sniffer
*/
#include "RCSwitch.h"
#include <stdlib.h>
#include <stdio.h>
RCSwitch mySwitch;
int main(int argc, char *argv[]) {
// This pin is not the first pin on the RPi GPIO header!
// Consult https://projects.drogon.net/raspberry-pi/wiringpi/pins/
// for more information.
int PIN = 2;
if(wiringPiSetup() == -1)
return 0;
mySwitch = RCSwitch();
mySwitch.enableReceive(PIN); // Receiver on inerrupt 0 => that is pin #2
while(1) {
if (mySwitch.available()) {
int value = mySwitch.getReceivedValue();
if (value == 0) {
printf("Unknown encoding");
} else {
printf("Received %i\n", mySwitch.getReceivedValue() );
}
fflush(stdout); // Add this line to flush the previous printf()
mySwitch.resetAvailable();
}
}
exit(0);
}
And if you run the RFSniffer tool with sudo permission, you can execute with :
sudo ./RFSniffer | sudo tee rfsniffer.log
OR
sudo sh -c './RFSniffer >> rfsniffer.log'