c = rgData.length
var pA = 0 // previos encoder A value
var iA = 0 // last encoder A rising edge
var cnt = 0  // starting step count
for(var i = 0; i < c; i++){
    fA = 1&(rgData[i]<<0)  //  live encoder-A signal on channel DIO = 0
    fB = 1&(rgData[i]<<1)  //  live encoder-B signal on channel DIO = 1
    if(fA==1 && pA==0){ // encoder A rising edge
        if(fB==1){ // encoder B level at time of A-rising edge indicates direction
            cnt++
        }
        if(fB==0){ // encoder B level at time of A-rising edge indicates direction
            cnt--
        }
        for(var j = iA; j < i; j++){ // assign value (step count) to previous A cycle
            rgValue[j] = cnt
            rgFlag[j] = 1
        }
        iA = i
    }
    pA = fA
}
for(var j = iA; j < c; j++){ // fill the remaining samples
    rgValue[j] = cnt
    rgFlag[j] = 1
}