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These days there is a limited amount difference under the hood between a CISC processor like the x86 series and a RISC processor. They're mostly RISC under the hood but a CPU like the x86 has a layer of microcode embedded in the processor which implements the complex instructions.

http://www.heyrick.co.uk/assembler/riscvcisc.html

I had a quick look. Whoever wrote it seems to have conveniently forgotten the early 90s advert when Apple claimed to be selling the "World's first RISC computer".

Those of us who owned Acorns thought it was more than a bit dodgy - but especially funny when Acorn took out an advert in the Times welcoming Apple to the world of RISC... http://www.heyrick.co.uk/assembler/history.html

It's a real shame that Acorn pulled out of the personal computer market. I've used lots of other operating systems and processors since my early computer experiences with Acorns. Not one of them has been anywhere near as well-designed.

Yeah, me too, I loved the 6502, 68000, then ARM. I really need to have a go on the PowerPC. It looks cool too.

Oooh, and there's one right in this Mac!! ;-)

One thing that I haven't seen mentioned is that Ceefax at one time was used to distribute computer software, as a kind of poor-man's Internet/BBS (download only). The primary use was to freely distribute software associated with the educational programs on the BBC to schools around the country.

A Teletext adapter was available for the BBC micro computer (Acorn) that would allow software to be downloaded from the Ceefax service. The concept was called Telesoftware, although the inherent limitations of teletext meant that it never really caught on.

Ahh, spoke to soon - a quick Google led me here:

"A very special feature of the ARM processor is its conditional execution. We are not talking your basic Branch if Carry Set, the ARM takes this a logical stage further to mean XXX if carry set - where XXX is just about anything."

Don't know what your best option for an assembler/dev environment would be for the Tungsten: I haven't played with ARM code outside the Gameboy Advance and back in the days of Acorn, but these links might prove useful:

• ARM Tutorial - Acorn-centric, but some of the basic stuff should still be relevant...
• Selection of ARM assembler documents
• ARM lecture notes
• GBAdev's links to ARM documentation

All highend processors are now RISC.

The difference is that 6x86 has more instructions stored interally that are basically translated to a set of RISC calls through microcode. :-)

This means that Photoshop was faster on a Mac not because of a faster processor, but because the restrictions on what the processor can do for you are tighter and they therefore had to write better code for that processor.

If they had limited themselves to Motorola-style set of instructions on the 6x86 (of course some are simply missing and one would have to code around that little problem), I have no doubt that photoshop would have kicked ass on the 6x86.