Comparing the Papilio One with the Pro

[MartyMacGyver]

Beyond the various new features per the wiki page, how does the Papilio Pro stack up to the One (500K) in terms of its capacity to contain a given logic design, particularly the Arduino and ZPUino cores?

 

My point of reference is this spec sheet. The One's XC3S500E appears to have far more slices compared to the Pro's XC6SLX9 (even when considering the 2:1(?) difference in slice sizes between the newer Spartan-6 and the older Spartan-3), but of course there's the new DSPs and such as well in the 6.

Other than that, the Spartan-6 seems to have slightly fewer logic cells and slightly more flip-flops (but do those numbers include what's in the slices, etc.?)

 

Thanks in advance, and if this is all covered elsewhere already just let me know... so far I haven't stumbled upon a head-to-head comparison of the Pro vs the One 500K with these details, and that'd be useful info for people switching to the Pro (or, like me, starting out with it).

 

[alvieboy]

Spartan6 has 6-input LUT, with two output, and S3E500 has only 4-input LUT, with one output. This allows you to pack more combinatorial logic into a single slice.

 

Due to this, it's hard to compare both.

 

S6LX9 has 5,720 6-input luts, bringing the total number of inputs to 34320

S3E500 has 9,312 4-input luts, bringing total number of inputs to 37248

 

So I'd say that for most designs (which are more LUT based than FF based) the S3E500 is somewhat larger.

 

Other thing I can tell you is that S6 is way faster than S3E, at least on ZPUino design. This might be related to the increased LUT packing,

 

Alvie

[MartyMacGyver]

Thanks, that helped me understand how to compare these. I also found this page with very similar information - the 6 appears to have the equivalent of 9152 4-input LUTs (using Xilinx's 1.6 factor), which in isolation is just a handful fewer than the 3E. Coupled with the other features the 6 is definitely superior, but this metric helps with design comparisons.

 

It'd be very interesting to see the footprints of ZPUino and Arduino on the S3E500 vs the S6LX9, given the indirect effectiveness gains in the 6.