Hi All

I'm trying to write a PS to control my Sky satellite box from my 9400 directly via TCP. I can connect fine, and using the information at [Link: github.com], I can read and write the data, but nothing happens. The relevant section in the nodejs .js is

function sendCommand(code, cb) {
var commandBytes = [4,1,0,0,0,0, Math.floor(224 + (code/16)), code % 16];

var client = net.connect({
host: host,
port: port || 49160
});

var l = 12;
client.on('data', function(data) {
clearTimeout(connectTimeoutTimer)
// Clear timeout
if (data.length < 24) {
client.write(data.slice(0, l))
l = 1;
} else {
client.write(new Buffer(commandBytes), function() {
commandBytes[1]=0;
client.write(new Buffer(commandBytes), function() {
client.destroy();
cb(null)
});
});
}
});

.. which I've replaced with

function onData(){
System.print("Ondata.");
receivedText = socket.read();
System.print(receivedText.length)
var len =12;
if (receivedText.length < 24){
socket.write(receivedText.slice(0,len));
len = 1;
} else {
System.print("Writing Data")

socket.write [0x04,0x01,0x00,0x00,0x00,0x00,0xE0,0x00];
socket.write [0x04,0x00,0x00,0x00,0x00,0x00,0xE0,0x00];

socket.close;
socket=null;
}

}

I've just hardcoded code=0 in effect, so 0xE0 is Math.floor(224 + (code/16)) and 0x00 is code % 16. But, nothing happens. I'm guessing that you can't just write the hex values to the socket, but Buffer doesn't seem to exist in ProntoScript.

Any ideas how I could change this? Also, any ideas how to debug?

Thanks

pete S

Hi peteS
Did you check what errors you get on the debug panel and did you initialize the socket as described in the PS developer manual ?
It seems you have included a space after socket.write and used [ and ] instead of ( and ).
Use round brackets for writing to a socket, eg: AV_Socket.write("?V\r");
Rene

Hi Rene

Yes, with a bit of searching and judicious use of Wireshark, I got it sorted. Bottom line is that socket.write doesn't support writing a byte array - hence the []. Looking at wireshark, it just sends nothing at all. You need to convert it to a string.

Use ...

function ArrayToString(arr){

var stringToSend = '';
var i;
for (i = 0; i < arr.length; i++)
stringToSend += String.fromCharCode(arr[i]);
return stringToSend
}

then call

socket.write (ArrayToString([0x04,0x01,0x00,0x00,0x00,0x00,0xE0,0x00]));

Now have a fully working IP control version for the Sky box ...

pete S

Hi pete S

If you need to send hex data, this method will work as well:

socket.write("\x04\x01\x00\x00\x00\x00\xE0\x00");
socket.write("\x04\x00\x00\x00\x00\x00\xE0\x00");

or

var string_1 = "\x04\x01\x00\x00\x00\x00\xE0\x00";
var string_2 = "\x04\x00\x00\x00\x00\x00\xE0\x00";
socket.write(string_1);
socket.write(string_2);

or

var cmd_array = ["\x04\x01\x00\x00\x00\x00\xE0\x00", "\x04\x00\x00\x00\x00\x00\xE0\x00"];
socket.write(cmd_array[0]);
socket.write(cmd_array[1]);

or a combination, eg:

var cmd_array = ["\x01", "\x00"];
var string_header = "\x04";
var end_of_package = "\x00\x00\x00\x00\xE0\x00";
socket.write(string_header + cmd_array[0] + end_of_package);
socket.write(string_header + cmd_array[1] + end_of_package);

Just use \x before the hex and put it between "" since it has to be a string.

Rene

Yep - that's what I thought as well. That works fine for serial, but just doesn't send anything (according to wireshark) on a tcpsocket. Hence, the need to convert it to a string. Oh well, works now.

Hi pete S

I can confirm that all versions I mentioned above do work without any problem. Before posting those I made some tests with my Pronto with all four versions and everything worked as expected - if not for you, you will have an error elsewhere.

FYI: My 9600er is sending this code over a tcp-socket to a GC-100, and this converts it to serial. I have a RFX9600 as well and used similar codes before - and those worked as well.

Rene

Thanks Rene

Not sure what I was doing earlier - as you say, your form now works fine. Might have had a stray , in there I think....

Anyway, the form I'm using is now

writeText = "\x04\x01\x00\x00\x00\x00"+chr[Math.floor(224 + (code/16))]+chr[code % 16];
socket.write (writeText);

I've borrowed the chr[] array definition from Barry - nice easy lookup method.

So, all good there now. thanks for your help.

pete S

Here are some useful tips as well.

// Just copies pointer to function into variable chr.
var chr = String.fromCharCode;
// Invokes function chr (String.fromCharCode) with the arguments in parenthesis.
var result = chr(Math.floor(224 + (code/16)));

I sometimes do this as well.

var $f=false;
var $t=true;
var $b=' ';
var $c = '\r\n';
var $n = null;

Note that $n works as 'null' is a special value of a JavaScript Object. You cannot do the same for keyword/value 'undefined'.