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Altera_Forum's avatar
Altera_Forum
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16 years ago

Fixed Point or Floating point implementation

I need to implement closed loop controllers like multiple PID controller in FPGA. I also need to do some signal preconditioning and signal processing in fpga. I would like to know if its bett...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

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Thanks for your reply.

Is the IEEE VHDL 200X fixed point package by David Bishop a good one to start with if I use fixed point?

You are correct the floating point implementation takes up a lot of logic and clocks.

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Perfect place to start, but quartus doesnt support the 2008 version (yet)

You can get a version thats compatible with VHDL 93 here:

http://www.vhdl.org/fphdl/

You can do fixed point with numeric_std package or if you have to, the std_logic_arith package, but the fixed point package can really help your sanity tracking fractional bits!