I'm new to the embedded development world and am looking to get my very first board.
After some research, I realize that there aren't many choices with FPUs. This is important in my project as I'm going to be doing quite a bit of floating point computations.
I found the Mini2440 which seems to run on the ARM920T core. This particular unit is perfect for my needs (decent pr开发者_运维问答ice, all the right I/O ports, and a touch screen to boot) but it seems that it doesn't have an FPU. I don't know how big of a penalty I'd be paying for FP emulation, so I'm unsure of whether to pull the trigger on this one.
That said:
- Can someone please confirm whether this product (Mini2440) has an FPU or not?
- My project will do image capture and analysis. Does anyone have any experience with running things like OpenMP on such platforms?
- Please suggest any other similar boards in the ≤ $200 price range that have an FPU.
- This world is new to me. Any other advice or things I should be aware of is much appreciated.
Fixed Point math can do nearly everything Floating point can and ARM processors with their shift optimization love fixed point. I haven't had a FPU in so long that coding Fixed Point is second nature to me. And even better, Fixed math quite often is more accurate.
In short, don't write off a board because it doesn't have an FPU. :)
Did you look at the BeagleBoard ? Its ARM CPU has VFP for floating point and also NEON for SIMD floating point. Cost is around $200.
I can't give you 100% confirmation, but I'm 99% sure that board's processor doesn't have an FPU; in that target market, it would be mentioned explicitly in the processor datasheets if it were present.
As an answer to a side-question: We were recently doing a bit of benchmarking that ended up comparing performance with an FPU to performance with compiler floating-point emulation without the FPU. Ended up with about a 100x difference in speed.
So, yes, it works -- but no, you don't want to do that for more than very occasional computations. As Michael notes, using fixed-point math is a much more attractive option for computations on embedded processors that don't have FPUs.
No touchscreen, not sure why that matters, the beagleboards serial port is screwy but you still get a terminal, or go with a hawkboard which is also omap based, half the price and designed a little better, has ethernet so you can vnc in and get a full gui without double or tripling the price on a lcd touchscreen.
Instead of going with floating point arm, use the on chip (omap) dsp for that. TI float is superior to IEEE in so many ways.
Try the Samsung S3C6410 with FPU. And the Witech OK6410 board with Samsung S3C6410 cpu and 4.3" LCD, $139 only
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