Can I implement advanced control algorithm with floating-point computations in Ni 7831R ?

Hi,
I plan to use a Ni 7831R to control a MIMO nano-positioning stage with servo rate above 20kHz. The control algorithm is based on robust control design and it is much more complex than PID. it also includes floating-point caculations. Can I implement such algorithm with Ni 7831R?
By the way, is there any way to expand the FPGA gates number for Ni 7831R? Suppose I run out of the FPGA gates (1M), can I add more FPGA gates by buying some different hardware?
Thanks
Jingyan
Message Edited by Jingyan on 08-22-2006 01:45 PM

Jingyan,
as long as there is no GPU core implemented on the FPGA these devices only support integer arithmetic. NI's FPGA targets currently don't contain a GPU core so there is no native floating point arithmetic available.
Still there are several options to implement floating point arithmetic on your own or to work around this target specific limitation. Here are some links that might help:
Floating-Point Addition in LabVIEW FPGA
Multiplying, Dividing and Scaling in LabVIEW FPGA
The NI 7831R uses an 1M FPGA. If your application requires more gates the NI 7833R (3M) is a good solution.
I hope that helps,
Jochen Klier
National Instruments Germany

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