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Offline koaftder

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Re: X1000 xmos
« Reply #74 from previous page: January 29, 2012, 01:24:44 AM »
Quote from: Iggy;678046

Have you actually looked into XMOS programming?
Its not just hacker friendly, its relatively easy to use (and quite flexible).
Its just not that fast.


Yes, I used the XS1L1 in a commercial product, where I designed the hardware and wrote the firmware. I'm very familiar with it.
 

Offline koaftder

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Re: X1000 xmos
« Reply #75 on: January 29, 2012, 01:31:47 AM »
Quote from: Iggy;678046

Its just not that fast.


For a microcontroller, it's no slouch.
 

Offline Iggy

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Re: X1000 xmos
« Reply #76 on: January 29, 2012, 01:57:11 AM »
Quote from: koaftder;678048
For a microcontroller, it's no slouch.

That I will agree with you on.

Its also a little easier to implement then most microcontrolleers.

But, you're also right to point out that development hasn't moved as fast as you might expect.
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Offline Karlos

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Re: X1000 xmos
« Reply #77 on: January 29, 2012, 02:01:37 AM »
Quote from: koaftder;678044
Is it really? What's hacker friendly about a PCIe connector?


PCIe ribbon cables, for one. Since it's a point to point "many serial lanes" protocol, rather than some tricky to time parallel one, breaking out of a PCIe slot for some hacking probably involves getting a PCIe ribbon cable, chopping one end off and soldering the signal lines to your nefarious homebrew hardware...
int p; // A
 

Offline koaftder

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Re: X1000 xmos
« Reply #78 on: January 29, 2012, 02:02:59 AM »
Quote from: Iggy;678053
That I will agree with you on.

Its also a little easier to implement then most microcontrolleers.

But, you're also right to point out that development hasn't moved as fast as you might expect.


You won't get any disagreement from me on those points, I think it's a great little micro. Earlier in this thread I state why I used it in a commercial project. I do, however, think it's little more than a gimmick in the A1X1K and I expect that it'll get about as much use as the FPGA in the sam.
 

Offline koaftder

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Re: X1000 xmos
« Reply #79 on: January 29, 2012, 02:05:38 AM »
Quote from: Karlos;678055
PCIe ribbon cables, for one. Since it's a point to point "many serial lanes" protocol, rather than some tricky to time parallel one, breaking out of a PCIe slot for some hacking probably involves getting a PCIe ribbon cable, chopping one end off and soldering the signal lines to your nefarious homebrew hardware...


Looks like a pain but your suggestion is the best one i've heard of yet to interface to that thing.
 

Offline vidarh

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Re: X1000 xmos
« Reply #80 on: January 29, 2012, 04:17:01 PM »
Quote from: koaftder;677763
You do have an entire processor core in the A1X1K doing nothing clipping along at 2GHz.


Which still makes it a massive pain to keep latency down to the level the XMOS can without hand-writing asm with no OS support, and locking yourself into a situation where your code won't work whenever someone cooks up another use for that core.

Trying to do multi-threaded IO on a PPC core with the kind of latency the XMOS can achieve, for example, would be a rather impressive demonstration, if it's possible at all. They're not designed for that at all.

Throughput is another matter - there it'd totally thrash the XMOS chips.

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It is absolutely telling. It tells us that people aren't actually interested in this enough to start hacking.


All it tells us is that people aren't interested in hacking Amiga-specific projects with the standalone units. I'm in that category. I want to play with it more, but what interests me is exploring what I can do with the integration, not really the standalone units.

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You're right that you don't need XC, but you're wasting your time and making trouble for your self for no good reason by ignoring it. You'd also be shutting yourself off from using a large base of library code the Xcore community has developed and put out for others to use. The ASM documentation sucks, you'll find yourself on the forums begging XMos engineers for help.


The asm documentation coupled with assembler output from the XC compiler is more than sufficient. The channel extensions are simply and straightforward, and I had no problems finding out how to do it in asm. Have you actually looked at it? I have. It's a tiny amount of work.

As for "shutting yourself off", if that's so critical I doubt you'll find many people here who don't *have* other hardware if they absolutely need it, but even if not, converting XC source is not generally a lot of work - the syntax extensions are tiny.

And the "good reason" is to avoid a proprietary compiler and tools that aren't available everywhere you might want to use them.

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Good for you, and you'll not have access to the simulator and code profiling tools.


The simulator can be run from the command line. No need to run Eclipse. Profiling can be done with the GNU toolchain, no need to run Eclipse (and/or you can do it with instruction traces from the simulator).

Have you even bothered looking at the command line tools available?

Though some of the tools including the simulator is still closed source so there you would be stuck with running them on a Windows/Mac/Linux box unless they're getting it ported.

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But who are we kidding here, you've never used this stuff and you'll never do any of the things you mentioned in the previous paragraph. Haven't we had this conversation before on that other site... like a year ago?


I've used it. But I'm one of those that don't have all that much interest in the standalone units, at least not enough to compete with the far too many other projects I have ongoing.

And yes, we've had this conversation before, and we still don't have the X1000 and so like many others I still don't have a platform that'll make it interesting for me to invest time in it.

When I have one, I'll play with it. Whether or not anything "useful" will come of it, we'll have to wait and see, but I'm not buying an X1000 for productivity, but for fun -  otherwise there'd be no way I'd be willing to spend that much money on it.
 

Offline koaftder

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Re: X1000 xmos
« Reply #81 on: January 30, 2012, 01:03:03 AM »
Quote from: vidarh;678120
Which still makes it a massive pain to keep latency down to the level the XMOS can without hand-writing asm with no OS support, and locking yourself into a situation where your code won't work whenever someone cooks up another use for that core.

The latency thing isn't very interesting. There isn't a damn thing you can do with an XCore micro controller that you can't do with a whole slew of other devices (obviously, we've been doing just that for decades). The only real advantage is that the architecture makes for some really simple and easy design albeit at a high per unit cost and with a chip that has an atrocious energy profile.


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The asm documentation coupled with assembler output from the XC compiler is more than sufficient. The channel extensions are simply and straightforward, and I had no problems finding out how to do it in asm. Have you actually looked at it? I have. It's a tiny amount of work.

Yes I have looked at it, I wrote a BASIC compiler for it as well as a FORTH interpreter and quite frankly I think you're making this stuff up. If you think the documentation is sufficient I'd have to assume you've done nothing beyond the most trivial of things with it. There are all kinds of gaping holes in the documentation describing the execution environment and in order to get a complete view of how this chip works you will have to ask a lot of questions.  

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And the "good reason" is to avoid a proprietary compiler and tools that aren't available everywhere you might want to use them.

The compiler source is slated to be released some time in the future when they get the language spec finalized.

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I've used it. But I'm one of those that don't have all that much interest in the standalone units, at least not enough to compete with the far too many other projects I have ongoing.

And yes, we've had this conversation before, and we still don't have the X1000 and so like many others I still don't have a platform that'll make it interesting for me to invest time in it.

When I have one, I'll play with it. Whether or not anything "useful" will come of it, we'll have to wait and see, but I'm not buying an X1000 for productivity, but for fun -  otherwise there'd be no way I'd be willing to spend that much money on it.

Confused, you say in one sentence that you've used it, and in another that you'll have to wait for the A1X1K before you'll have a chance to work with it. Which is it? Have you done anything with XCore micro controllers or not?

I know you think you've got this stuff figured out, but you obviously don't.