A-4 X1 CODER 100-101116
N L J H F D C B A
G R R R R T T T T
r e e e e P P P P
n d d d d
The X1A code is a shift register with the following equation:
1 + X6 + X8 + X11 + X12
The X1B code is a shift register with the following equation:
1 + X1 + X2 + X5 + X8 + X9 + X10 + X11 + X12
Where the exponents are the tap locations that are combined in an or gate and fed back to the input.
The X1 code is formed by the MOD 2 combination of X1A and X1B (i.e. a Gold Code).
I would expect to find a couple of 12 bit shift registers on this board with each bit's output brought out to a pin and some big OR gates and an external or gate to sum the codes.
|AM25LS194APC||F 93S47PC||DM74LS32N||TI SN74LS123N|
|AM25LS194APC||93S48 PC||TI SN74LS37N||header rcrcrcrc|
|AM25LS194APC||93S47PC||Beckman 899-1-R270||TI SN74LS123N|
|2000052 93427pc PROM?||F 93S47PC||AM25LS163PC||AM25LS164PC|