Specifications
GAL20VP8
Simple Mode
In the Simple mode, macrocells are configured as dedicated inputs
or as dedicated, always active, combinatorial outputs.
All outputs in the simple mode have a maximum of eight product
terms that can control the logic. In addition, each output has pro-
grammable polarity.
Pins 1(2) and 12(14) are always available as data inputs into the
AND array. The center two macrocells (pins 17(20) & 19(23)) can-
not be used in the input configuration.
The JEDEC fuse numbers including the UES fuses and PTD fuses
are shown on the logic diagram.
Vcc
Combinatorial Output with Feedback Configuration
for Simple Mode
- SYN=1.
- AC0=0.
- XOR=0 defines Active Low Output.
- XOR=1 defines Active High Output.
- AC1=0 defines this configuration.
- AC2=1 defines totem pole output.
- AC2=0 defines open-drain output.
- All OLMC
except
pins 17(20) & 19(23) can be
configured to this function.
Combinatorial Output Configuration for Simple Mode
XOR
Vcc
XOR
- SYN=1.
- AC0=0.
- XOR=0 defines Active Low Output.
- XOR=1 defines Active High Output.
- AC1=0 defines this configuration.
- AC2=1 defines totem pole output.
- AC2=0 defines open-drain output.
- Pins 17(20) & 19(23) are permanently configured to
this function.
Dedicated Input Configuration for Simple Mode
- SYN=1.
- AC0=0.
- XOR=0 defines Active Low Output.
- XOR=1 defines Active High Output.
- AC1=1 defines this configuration.
- AC2=1 defines totem pole output.
- AC2=0 defines open-drain output.
- All OLMC
except
pins 17(20) & 19(23) can be
configured to this function.
Note: The development software configures all of the architecture control bits and checks for proper pin usage automatically.
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