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Chapter 4: Getting Started
System Generator Fixed-Point Quantization
Xilinx fixed-point data types are defined by specifying the total number of bits then specifying the location of the
binary point. The difference, which represents the number of bits to the left of the binary point, are the integer bits
for ufixed numbers and the integer bits plus sign bit for signed numbers. Xilinx FPGAs do not require that fixedpoint numbers fall in pre-defined 8 bit boundaries as is the case with DSP processors. The logic can grow bit-by-bit
to accommodate the required fixed-point precision.
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System Generator for DSP Getting Started Guide
UG639 (v 14.3) October 16, 2012