Aiken code
An alternative form of the Binary Coded Decimal (BCD) system for encoding numbers. Where BCD encodes each decimal digit in normal binary, Aiken code uses the encoding shown below. This is supposed to be less prone to corruption.
The following table shows the encoding of each decimal digit, D, in BCD and Aiken code:
D BCD Aiken 0 0000 0000 1 0001 0001 2 0010 0010 3 0011 0011 4 0100 0100 5 0101 1011 (inverted 4) 6 0110 1100 (inverted 3) 7 0111 1101 (inverted 2) 8 1000 1110 (inverted 1) 9 1001 1111 (inverted 0)
The Aiken code was probably designed by Howard Aiken in the 1940s or 1950s for use in data transmission.
Compare: Gray code.