Interfacing with FPU

Forum 2005-2010 (read only) Hardware Interfacing
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Has anyone tried interfacing their Arduino with one of these?:

It's a floating point co-processor made for microntrollers with I2C, SPI, and plain old serial inputs. Essentially you pass the code for the FPU during the setup process then call it by sending serial and receiving serial data.

I've got one on the way, so I'll be happy to be the first guinea pig, but I would appreciate any info up front.

I really got it because I am working on a GPS project with the Arduino and the lack of floating point arithmetic was going to be a big coding problem. Not only does this FPU do the floating point, but it also has it's own external serial interface and it can read serial NMEA data straight from a GPS or GPS module and has well documented functions for the string operations to dissect the NMEA output and a lot of references on DMS to decimal degrees to radians, great circle distance and bearing calculations, and a lot more. I'm just hoping I can get it working - I may be asking a lot of questions here on the forums. :o

Manufacturer Info: Micromega: uM-FPU V3.1

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You can do floating point calculation on the Arduino, btw. It's only printing them over the serial port that doesn't work, but there are ways around that (e.g. see this post to the developers mailing list: http://mail.arduino.cc/pipermail/developers_arduino.cc/2007-September/000427.html). I'm sure an FPU is still useful for some things though.

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The instruction set on the FPU looks intriguing, plus it will nearly automate much of GPS communication and decoding, which will free up the Arduino for handling several other tasks. I was fairly worried about splitting up the time of reading the NMEA data and doing some other I2C and I/O at the same time, but this might do the trick.

Plus it should be much faster...