GAL16V8 Datasheet, PDF (4/22 Pages) Lattice Semiconductor – High Performance E2CMOS PLD Generic Array Logic

Specifications GAL16V8
Registered Mode
In the Registered mode, macrocells are configured as dedicated Dedicated input or output functions can be implemented as sub-
registered outputs or as I/O functions.
sets of the I/O function.
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.
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.
CLK
DQ
XOR
Q
OE
XOR
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.
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