7bits x 16rows Latch Register for Signboard

On this page, I will introduce a latch register for "Signboard 2" using PIC.
This is the latch circuit for the LED of the signboard.
There is a latch register by the general logic IC(Like 4034B : 8 Bit Universal Bus Register).
To latch with 8bits x 16rows, 16 pieces of IC are needed. Their IC is 24 pins generally.
To mount them, a lot of space is needed.

The circuit to introduce here is the circuit which used two CPLD(XC9572-PC84).
In one CPLD, it is made to have the latch function of 7 bits x 8rows by the limitation on the number of the pins.

The binary code of 4 bits is used for the selector to specify a row.
Each IC has 4-16 selector. It controls eight rows which are different in each IC.

Side A

Side B

Operating state table
0000Q0 = DIN
0001Q1 = DIN
0010Q2 = DIN
0011Q3 = DIN
0100Q4 = DIN
0101Q5 = DIN
0110Q6 = DIN
0111Q7 = DIN
1000Q8 = DIN
1001Q9 = DIN
1010Q10 = DIN
1011Q11 = DIN
1100Q12 = DIN
1101Q13 = DIN
1110Q14 = DIN
1111Q15 = DIN

CLK is effective when changing into L from the H.