To make this a bit more concrete, using memcpy to copy 1KB of word aligned data from one location to another is 2.55 times faster on xCORE-200 (assuming at least 5 cores are in use). The speed up comes from the use of double word load and store instructions, dual issue and increased instruction fetch bandwidth.infiniteimprobability wrote:There are a few other instructions which will boost speed too - especially load/store double (64b). This will really help on memcpy, dsp and push/pops.
New XMOS chips??!
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I assume that 2.55x speedup is from 1-lane mode to 2-lane
mode, both on 200 parts? So that makes 2.04x speedup
over G/L (assuming max. 5 threads). G/L can do the loop
in 4 thread cycles, so 1 byte per thread cycle (no loop
unrolling); 200 can do it 2 bytes per thread cycle? Nice :-)
mode, both on 200 parts? So that makes 2.04x speedup
over G/L (assuming max. 5 threads). G/L can do the loop
in 4 thread cycles, so 1 byte per thread cycle (no loop
unrolling); 200 can do it 2 bytes per thread cycle? Nice :-)
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Thanks XMatt does this mean that the X*F chips (with internal flash) are based on a Quad SPI tile bonded to ports 1B,4B & 1C. If so can these pins be used externally, or is something more sophisticated happening?XMatt wrote:Yes QSPI boot, the embedded flash parts have QSPI flash internally.Folknology wrote:Thanks Xmatt
Does the boot actually use QSPI to improve performance as well as overlays?
I am trying to work out if I can use these pins as I would like to be able to.
regards
Al
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The 2.55x speed up compares an optimized dual issue memcpy running on a xCORE-200 logical core to an optimized single issue memory running a XS1-L/G logical core assuming that the logical cores are running at the same rate. If you have 5 or more cores active then the cores will be running at the same rate. If have less than 4 cores active the xCORE-200 cores will be running at 100MHz instead of 125MHz so the speed up will only be 2.04x.segher wrote:I assume that 2.55x speedup is from 1-lane mode to 2-lane
mode, both on 200 parts? So that makes 2.04x speedup
over G/L (assuming max. 5 threads). G/L can do the loop
in 4 thread cycles, so 1 byte per thread cycle (no loop
unrolling); 200 can do it 2 bytes per thread cycle? Nice :-)
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Ah, you're talking about a full C library memcpy routine,
so that includes setup overhead etc.
We don't have manuals yet so I have to guess a bit; a fun
game :-)
Looking only at the core of an unrolled copy loop, on L/G
that is [ load / store / fetch no-op ], so 3 cycles per word,
12 cycles for 4 words. To get about 2.55x speedup over
that, my best guess is 2.4x, via [ ll / ss / ll / ss / fetch ].
Is that about right?
Pretty awesome :-)
so that includes setup overhead etc.
We don't have manuals yet so I have to guess a bit; a fun
game :-)
Looking only at the core of an unrolled copy loop, on L/G
that is [ load / store / fetch no-op ], so 3 cycles per word,
12 cycles for 4 words. To get about 2.55x speedup over
that, my best guess is 2.4x, via [ ll / ss / ll / ss / fetch ].
Is that about right?
Pretty awesome :-)
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A low-cost kit should soon be available:
https://www.xmos.com/support/boards?pro ... 0&secure=1
Version 14.0 of xTIMEcomposer Studio, which supports the new devices, is available now:
http://www.xmos.com/support/tools
The Timing Analyser can be used to check performance details.
https://www.xmos.com/support/boards?pro ... 0&secure=1
Version 14.0 of xTIMEcomposer Studio, which supports the new devices, is available now:
http://www.xmos.com/support/tools
The Timing Analyser can be used to check performance details.
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I got the
today.
Anyone else?
I'm playing around with the gigabit Ethernet example and virtual COM port here :)

today.
Anyone else?
I'm playing around with the gigabit Ethernet example and virtual COM port here :)
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How did you get it?
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With cables! :-)lilltroll wrote:I got the [nice new board] today.
Anyone else?
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So, can anyone tell me how to get one of these boards? Pricing?
Cannot find any listing on Element14/Farnell or Digikey.
Cannot find any listing on Element14/Farnell or Digikey.