The AN/UYK-8 was a UNIVAC computer. It used the same 30-bit words and instruction set as the AN/USQ-17 and AN/USQ-20 Naval Tactical Data System (NTDS) computers, but could have two processors instead of just one.
Instructions were represented as 30-bit words, in the following format:
f 6 bits function code j 3 bits jump condition designator k 3 bits partial word designator b 3 bits which seven index register to use (B0=non used) s 2 bits which S (5bits) register to use S0,S1,S2,S3(P(17-13)) y 13 bits operand address in memory memory address=Bb+Ss+y=18bit(262144Words)
Numbers were represented as full 30-bit words, this allowed for five 6-bit alphanumeric characters per word.
The available processor registers were:
- one 30-bit arithmetic (A) register.
- a contiguous 30-bit Q register (total of 60 bits for the result of multiplication or the dividend in division).
- seven 30-bit index (B) registers.