6

Specifications GAL20V8

In the Complex mode, macrocells are configured as output only or

I/O functions.

Architecture configurations available in this mode are similar to the

common 20L8 and 20P8 devices with programmable polarity in

each macrocell.

Up to six I/Os are possible in this mode. Dedicated inputs or outputs

can be implemented as subsets of the I/O function. The two outer

most macrocells (pins 15 & 22) do not have input capability. De-

signs requiring eight I/Os can be implemented in the Registered

mode.

All macrocells have seven product terms per output. One product

term is used for programmable output enable control. Pins 1 and

13 are always available as data inputs into the AND array.

The JEDEC fuse numbers including the UES fuses and PTD fuses

are shown on the logic diagram on the following page.

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

Combinatorial I/O Configuration for Complex Mode

- SYN=1.

- AC0=1.

- XOR=0 defines Active Low Output.

- XOR=1 defines Active High Output.

- AC1=1.

- Pin 16 through Pin 21 are configured to this function.

Combinatorial Output Configuration for Complex Mode

- SYN=1.

- AC0=1.

- XOR=0 defines Active Low Output.

- XOR=1 defines Active High Output.

- AC1=1.

- Pin 15 and Pin 22 are configured to this function.

XOR

XOR

Complex Mode