DS-FND-BSX-PC Xilinx Inc, DS-FND-BSX-PC Datasheet - Page 185

• Manufacturer Part Number: DS-FND-BSX-PC
• Description: FOUNDATION BASE SYS W/SYN EXPRES
• Manufacturer: Xilinx Inc
• Type: Foundation Systemr

Specifications of DS-FND-BSX-PC

• For Use With/related Products: Xilinx Programmable Logic Devices
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 122-1185

State Machine Designs
Encoding for CPLDs
CPLD devices generally implement binary-encoded state machines
more efficiently. Binary encoding uses the minimum number of
registers. Each state is represented by a binary number stored in the
registers. Using as few registers as possible usually increases the
amount of combinatorial logic needed to interpret each state.
CPLD devices have wide gates and a large amount of combinatorial
logic per register, so it is best to start with binary encoding. If the
complexity of the state machine logic is such that binary encoding
exhausts all product term resources of a CPLD, try a slightly less fully
encoded state machine.
The syntax used to specify one-hot encoded state machines for
FPGAs is also supported for CPLD designs.
Foundation Series 2.1i User Guide
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