RedManchesterCode

Extension

//bigger number require more number of bits

RedManchesterCode(11).encode([1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1]);  //compare table in wikipedia article

​

a= RedManchesterCode();

a.encode([0, 1, 1, 1, 0, 0, 1, 0]);

a.encodeValue(114);  //same but different

a.encodeArray([114, 114, 5]);  //use this method for longer arrays

​

//if used as an audio signal it is often preferred to normalize the values -1 to 1.

//here is a simple way to do that normalization...

RedManchesterCode(11).encode([1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1])*2-1

​

//--sound examples

​

//although this is not 100% correct because of the byte boundaries

//the example just sequence manchester encoded bytes.

(

SynthDef(\redBitsPlayer, {|out= 0, amp= 1, rate= 1000|

    var numBits= 8*2;  //double because of manchester encoding

    var data= Control.names([\data]).ir(Array.fill(numBits, 0));

    var src= Duty.ar(1/rate, 0, Dseq(data*2-1++0), 2);  //zero padded because doneAction2 is not stopping sample accurate

    OffsetOut.ar(out, src*amp!2);

}).add;

)

​

//test counter

(

t= 2400;  //datarate

Routine.run({

    var encoder= RedManchesterCode(8);

    inf.do{|i|

        var byte= (i%256).asInteger;

        var data= encoder.encodeValue(byte);

        s.bind{

            Synth(\redBitsPlayer, [\out, 0, \data, data, \amp, 0.3, \rate, t]);

            ("playing:"+byte+data).postln;

        };

        (1/t*16).wait;

    };

});

)

​

//a more accurate example rendering the 0-255 counter data in advance, normalizing and loading it to a buffer

//stutter(8) means eight samples per data bit

b= Buffer.sendCollection(s, RedManchesterCode().encodeArray((0..255)).stutter(8)*2-1);

b.play;

b.free;

​

//it is also possible to skip this class and do manchester code directly in the synthdef...

(

SynthDef(\redManchesterEncode, {|out= 0, amp= 1, rate= 1000|

    var numBits= 8;

    var data= Control.names([\data]).ir(Array.fill(numBits, 0));

    var clock= Dseq(#[1, 0], numBits);

    var src= Duty.ar(1/rate, 0, Dseq([Dstutter(2, Dseq(data)).bitXor(clock)*2-1, 0]), 2);

    OffsetOut.ar(out, src*amp!2);

}).add;

)

Synth(\redManchesterEncode, [\data, 114.asBinaryDigits, \amp, 0.3]);

//record the result and compare with RedManchesterCode().encodeValue(114)