Wakefield show

Informal forum to keep you all informed on development progress

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Wakefield show

Post by admin » Tue May 24, 2005 2:45 am

Right, it's probably about time that I put a little progress report up here, so I thought I'd at least summarise the stuff that we've told various people at the show (thank you all for coming along to have a chat, it's always good to meet people in person and discuss ideas, suggestions, problems etc.)


As has been reported on drobe and TIB (in somewhat embarrassing, adulatory language thanks to monkeyson :( ) I got Aemulor's ARM610 engine running on the a9home at the show which is great. A reflection more upon the progress of Adjust32 and the a9home hardware (I just ran everything over the ShareFS network from my own development machine!) than upon Aemulor itself.

In fact, it took only about 4 hours to read through Aemulor and prevent any use of the hardware breakpointing (which the ARM9 CPU core does not provide) used by the StrongARM engine, and to make sure that there weren't any other XScale dependencies.

I then had to do a little more work at the show to avoid memory address conflicts between the 26-bit areas that Aemulor provides (normally at the standard RO4 addresses) and the 32-bit areas which that particular Adjust32 build provides at RO4-compatible addresses too.

And then, somewhat to my surprise, it worked; which was quite a relief since the RISC OS press somehow managed to choose that moment to appear, and I had quite an audience to witness the event. Thanks ;)

I'm pretty confident that the latest build of Aemulor Pro would in fact run Sibelius 7 on the a9home (I'd neglected to disable some prototype code at the show), though I don't yet have the hardware to confirm this.


Not very much to say, except that I finally finished some software. Yippee! :E

Well, released it anyway. Geminus, being modular, and having many acceleration features still planned, is - of course - not finished as such. But I'm using it constantly and I'm very glad that I wrote it.

Geminus is on sale now, and can be purchased from the website:


and time-limited demo builds can be downloaded from:


Of course you'll need to buy a graphics card before you try out the multi-monitor support. I'm a great fan of try-before-you-buy, but there's not much I can do to help on that score ;)

Future developments planned for Geminus in the near future are to complete and release the API code and documentation so that other applications such as Cino, PCITV and perhaps third parties such as Kris Adcock and Spacetech (OHP), can commandeer the second screen for their own use.


Cino,... ah Cino. Well, I've been working on it again for the past 1-2 weeks, after finally finishing Geminus so it got a little bit faster before the show (now typically running at between 8.5fps and 12.5fps depending upon the video stream, with audio switched off).

Audio decoding is still quite inefficient at the moment, so that's an obvious target for tuning. In fact it's eating about 15% of the CPU time currently.

The important thing is that I've managed to reduce the cost of the motion compensation which is what was worrying me most because it was previously consuming about 30% of the CPU time, making it practically impossible to speed up the code by the necessary 3-4 times to achieve full-rate playback. So, having now reduced that to about 20% (more comparable with the other stages of the player), things are looking more promising.

The memory performance of the Iyonix remains a potential issue, but I think I can improve things by restructuring the video decoder to better utilise the CPU's data cache, in a way not dissimilar to the operation of hardware M/JPEG decoders which have a bank of SRAM memory of comparable size attached.

Of course, in the PC world, you just throw faster hardware at the problem, but we don't have that option.

It's a shame that I didn't quite manage to get Cino running on the a9home on Sunday (oweing, it would appear, to a slight fault in the current development build of the OS - if you saw a crashed a9home on the STD/Ad6 stand on Sunday afternoon, then it was probably me that crashed it! Sorry ;) ) Having, I believe, isolated this - thus helping STD/Ad6 a little, I hope - I had a build of Cino that
I was 99% certain would have run, and I really wanted to see how it performed by comparison with the Iyonix, but it was not to be. (Apologies to anyone at STD/Ad6 who may have heard me utter an expletive at that point!)

The future

What next? Well, I've promised to do a bit more work on Aemulor Pro, mainly aimed at getting some multimedia/educational CDs running for Bablake Junior School whose Iyonix collection project has been waiting upon our support for far too long :(

In parallel with that, and soon to be - I hope! - my only active project for a while is Cino which has been languishing for far too long and is much in need of my full attention so that I can concentrate on tuning the code to achieve what this CPU was never really intended to do ;)

Unless someone wants to make my life easier and supply me with datasheets for the nVIDIA chipset? Please? ;)

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Post by monkeyson » Wed May 25, 2005 9:24 am

Don't worry, I haven't registered www.adrianleesappreciationsociety.com just yet... ;)

Would it be easier to develop Cino for the A9home? Would it be easier to get documentation for the Silicon Motion processor? Would the USB DVD drive cause problems?

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Post by admin » Wed May 25, 2005 7:11 pm

monkeyson wrote:Don't worry, I haven't registered www.adrianleesappreciationsociety.com just yet... ;)
Well, that's a relief!
Would it be easier to develop Cino for the A9home?
There's some interesting hw in there that may help. I'd need to get my mitts on the box before I'd know for sure, though.
Would it be easier to get documentation for the Silicon Motion processor?
It was pretty easy, yes ;)
Would the USB DVD drive cause problems?
With the RO software structured as it is, I expect we'd have to waste a fair bit of CPU time waiting for the data to arrive, which could be an issue. It might prove necessary to stream the data onto the HD prior to watching anything :(

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Post by admin » Thu May 26, 2005 4:28 am

For the record my Cino build wouldn't have worked anyway because I'd built it for ARMv5, not ARMv4 :roll:

In fact, there is an ARMv4 build of Cino because I've had it running on my StrongARM RiscPC, though it's not very optimal at the moment and needs even more work than the Iyonix version ;)

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Wakefield show

Post by bablakejs » Fri Jun 10, 2005 1:54 pm

The future? (AemulorPro)

Nice to see you haven't forgotten us... but I want to replace 12 more RiscPCs, and I can't till I can run the Sherston titles on new Iyonixes in that yeargroup...

I need to press you now, because it is coming up to the end of the financial year, and if we don't spend it, we lose it!

Gary Locock
Bablake Junior School

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