Biquinary code is a seven-bit code with
error-detection properties. Each
decimal digit consist of five 0's and two 1's. It is however a
pretty stupid way of transmitting
binary information, because you use a lot more bits than you have to. adding a
parity bit is in most cases a far better way to implement error-detection.
One example of biquinary code compared to NBCD code:
dec qbinary BCD
0: 0100001 0000
1: 0100010 0001
2: 0100100 0010
3: 0101000 0011
4: 0110000 0100
5: 1000001 0101
6: 1000010 0110
7: 1000100 0111
8: 1001000 1000
9: 1010000 1001