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Finding RISC processors Answered

Hi all, I've spent a great deal of time reading up on microprocessors so I can get involved with such an activity. However, I have found great difficulties in finding a high performance RISC processor. Being in the UK, I can only find one or two providers with a limited range of processors, and that isn't just RISC ones. I also get a little swamped looking at manufacturer's websites. It's very strange they all seem to boast an architecture with XYZ Mhz of max performance, but on their spec tables there is no processor with this maxed figure shown and a lot of entries /fields are empty making 99% of their processors unknown in spec. Highly annoy and useless. I'm not looking for anything special in regards to added features to the processor (I find most of it unnecessary and as a means to charge more money, apologizes for my ignorance in this;)), just a basic chip that can process a lot (thus higher Mhz) is all im after. lower power consumption are a great/big bonus for me though. Of course, prices does matter (not £300) but i am aware what im looking at isnt a $1 chip If anyone can point me in the right direction, that would be great. I've found many processors (for example, arm cortex-a by sounds of things is perfect: Over 1ghz of performance. Only problem no one seems to be making them; to the public like us anyway. Looking for microcontrollers seems to be quite a difficult task, if anyone has resources, sites or retailer /suppliers (UK for me, but feel free to post other countries for other user's benefit) or anything that would help it would be appreciated. I dont want you to do my dirty work, just guide me in the right direction. On another subject, at least with arm processors I've read the speed rating; for example 500mhz, if you x3 it'll give the "real speed" due to that 3 phase of processing it does. making 500mhz more like <1.5ghz. of course, it isn't exactly x3, the point i'm making the processing performance is better due to the 3 phases? thank you for your time.

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lukus001
lukus001

12 years ago

Thanks for the replies everyone, much appreciated! Those links were useful, though it seems all the pretty chips are not for sale to the general public :(, boo! I've been looking at Actel's range, just have to find someone who sales the chips in the UK in a non-quote sales basis. gonna have a look at renesas a bit more too thanks again :)

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westfw
westfw

12 years ago

Yes, the high-end risc processors seem to be difficult to get in "experimental" form, except for very expensive 'development boards.' A fair amount of the experimentation seems to happen with mass-produced consumer devices that have been "hacked" to allow your software to run on them; most of the wireless routers seem to be ~200MHz ARM or MIPs boxes, and many are linux based and so have published source to help you get started. Cortex is pretty new, and remember that ARM is an intellectual property company. So a Cortex-A isn't an actual chip, it's a set of designs that they think will run 1GHz if implemented in an appropriate semiconductor process... The high end seems largely lost to Intel/AMD non-risc cpus. (hey, wait a minute - the PowerPC is RISC; just buy an old Macintosh!)

Lower end RISC is pretty easy to find; ARM7, Cortext M3... But generally less than 100MHz...

> I've read the speed rating; for example 500mhz, if you x3 it'll give the "real speed" due to that 3 phase of processing it does. making 500mhz more like <1.5ghz.

I don't think so. That lets them get down to one instruction per clock instead of 12 clocks like an 8051, but 'everybody does it', and in the end it's the clocks per instruction (or instructions per clock) number that you have to watch. All the high-end CPUs are above 1 ips. Even many low end microcontrollers do 1 instruction per clock.

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NachoMahma
NachoMahma

12 years ago

. This is the only one I've heard of, but I'm sure there are many others.