def bytes_from_file(filename, chunksize=8192):
    with open(filename, "rb") as f:
        while True:
            chunk = f.read(chunksize)
            if chunk:
                for b in chunk:
                    yield b
            else:
                break

FN = 'sample.dat'

RES = []
i = 0

Pon = []
Poff = []
res = 0
# example:
for by in bytes_from_file(FN):
    if not(i):
        a = int(by)
        A = math.floor(a/2)
        Poff.append(3000*( A & 0b1000000) >> 6)
        Pon.append(3000*(A & 0b0100000) >> 5)
        A = A & 0b0011111

    if not(i%2):
        b = int(by)
        #B = int('{:08b}'.format(b)[::-1], 2)
        B = int(b/2)
    else:
        a = int(by)
        A = math.floor(a/2)
        Poff.append(3000*( A & 0b1000000) >> 6)
        Pon.append(3000*(A & 0b0100000) >> 5)
        A = A & 0b0011111
        #AA = int('{:07b}'.format(A)[::-1], 2)
        #AA = int.from_bytes(A, 'big')

        C = (A << 7) | B
        #CC = (DD << 7) | AA
        #print(i/2,": ",c, a,b,". Corrected ",A,B,". Binary:",bin(A),bin(B),bin(D),bin(C))#bin(a),bin(b))
        #print(int(i/2),hex(b),hex(a),": ","\tBinary\t:",bin(a),bin(A),"\t",bin(b),bin(B),bin(D))#bin(a),bin(b))
        #print(int(i/2),": \t\t\t",bin(A),"\t",bin(B),"\t",bin(C),hex(C),C)
        RES.append(C-2048)
        #print(res)
        res = 0
    i+=1