Specifications GAL16V8

5

In the Registered mode, macrocells are configured as dedicated

registered outputs or as I/O functions.

Architecture configurations available in this mode are similar to the

common 16R8 and 16RP4 devices with various permutations of

polarity, I/O and register placement.

All registered macrocells share common clock and output enable

control pins. Any macrocell can be configured as registered or I/

O. Up to eight registers or up to eight I/O's are possible in this mode.

Dedicated input or output functions can be implemented as sub-

sets of the I/O function.

Registered outputs have eight product terms per output. I/O's have

seven product terms per output.

The JEDEC fuse numbers, including the User Electronic Signature

(UES) fuses and the Product Term Disable (PTD) fuses, are shown

on the logic diagram on the following page.

Registered Configuration for Registered Mode

- SYN=0.

- AC0=1.

- XOR=0 defines Active Low Output.

- XOR=1 defines Active High Output.

- AC1=0 defines this output configuration.

- Pin 1 controls common CLK for the registered outputs.

- Pin 11 controls common

OE for the registered outputs.

- Pin 1 & Pin 11 are permanently configured as CLK &

OE for registered output configuration.

Combinatorial Configuration for Registered Mode

- SYN=0.

- AC0=1.

- XOR=0 defines Active Low Output.

- XOR=1 defines Active High Output.

- AC1=1 defines this output configuration.

- Pin 1 & Pin 11 are permanently configured as CLK &

OE for registered output configuration.

Note: The development software configures all of the architecture control bits and checks for proper pin usage automatically.

DQ

Q

CLK

OE

XOR

XOR

Registered Mode