hardware dependent. They can also occur in hardware and yet be
missed by simulation.
VHDL issues for FPGA design
Initialization
Any default values of signals and variables are ignored. This
means that you must ensure that synchronous (or asynchronous)
sets and resets must be used on all flip-flops to ensure a stable
starting condition. Remember that synthesis tools are basically
stupid and follows a basic set of rules that may not always result in
the hardware that you expect.
Floating point numbers and operations
Data types using floating point are currently not supported by syn-
thesis software tools. They generally require 32 bits and the requi-
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