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32-bit Microcontroller for $1.00 -Guy Macon

Started by Guy Macon July 21, 2008
"Wilco Dijkstra" <Wilco.removethisDijkstra@ntlworld.com> wrote:

> >"JosephKK" <quiettechblue@yahoo.com> wrote in message news:tskn841juifoem0nnu69unba2levtouial@4ax.com... >> On Wed, 23 Jul 2008 11:10:34 +0100, "Wilco Dijkstra" >> <Wilco.removethisDijkstra@ntlworld.com> wrote: > >>>Some are more significant than others though... MIPS for example joined >>>the MCU game only recently, and they have (like PPC) major codesize >>>issues, so you need a bigger and more expensive device. >> >> Actually in my very limited experience CISC machines need much more >> initialization than Regular Instruction Set Computers. Moreover CISC >> needs much more protection from errant processes, and much more >> dedicated register saving. Code size may be a compiler issue or a >> practitioner issue. > >I meant ISA differences. Each instruction set has a different maximum >density (assuming perfect compilers). This density depends on how >many registers are available, how powerful instructions are, and how >they are encoded. > >The original RISCs like MIPS and PPC went for all out performance with >simple instructions, while ARM added more powerful instructions (such as >load/store multiple). The result is ARM has far better codesize (when I last >measured it, MIPS was about twice as big as ARM, even MIPS16 was
Got any references to support this? I work with both ARM7 and MIPS32 using the 'same' compiler (GCC 4.2.1) but I'm not under the impression that the code size for MIPS32 is considerably larger then for the ARM7. -- Programmeren in Almere? E-mail naar nico@nctdevpuntnl (punt=.)
"Nico Coesel" <nico@puntnl.niks> wrote in message news:488cc317.78543549@news.planet.nl...
> "Wilco Dijkstra" <Wilco.removethisDijkstra@ntlworld.com> wrote: > >> >>"JosephKK" <quiettechblue@yahoo.com> wrote in message news:tskn841juifoem0nnu69unba2levtouial@4ax.com... >>> On Wed, 23 Jul 2008 11:10:34 +0100, "Wilco Dijkstra" >>> <Wilco.removethisDijkstra@ntlworld.com> wrote: >> >>>>Some are more significant than others though... MIPS for example joined >>>>the MCU game only recently, and they have (like PPC) major codesize >>>>issues, so you need a bigger and more expensive device. >>> >>> Actually in my very limited experience CISC machines need much more >>> initialization than Regular Instruction Set Computers. Moreover CISC >>> needs much more protection from errant processes, and much more >>> dedicated register saving. Code size may be a compiler issue or a >>> practitioner issue. >> >>I meant ISA differences. Each instruction set has a different maximum >>density (assuming perfect compilers). This density depends on how >>many registers are available, how powerful instructions are, and how >>they are encoded. >> >>The original RISCs like MIPS and PPC went for all out performance with >>simple instructions, while ARM added more powerful instructions (such as >>load/store multiple). The result is ARM has far better codesize (when I last >>measured it, MIPS was about twice as big as ARM, even MIPS16 was > > Got any references to support this? I work with both ARM7 and MIPS32 > using the 'same' compiler (GCC 4.2.1) but I'm not under the impression > that the code size for MIPS32 is considerably larger then for the > ARM7.
It's well known MIPS32 has codesize problems due to its simple instructions. I measured it myself on a huge codesize benchmark, you can try doing the same for your code (although GCC is obviously not the best compiler for ARM, so the difference won't be as large). This is a good post from Anton comparing various backends of GCC showing that MIPS is the worst of all RISCs: http://newsgroups.derkeiler.com/Archive/Comp/comp.arch/2007-12/msg00433.html Wilco
On Mon, 21 Jul 2008 19:10:31 +0000, Guy Macon
<http://www.GuyMacon.com/> wrote:

> > > >While researching something else, I ran into the >following rather interesting opinions: > >Consolidating the MCU market around the ARM architecture >("It's inevitable. ARM's Cortex-M3 processor core is going >dominate the MCU market.") >http://www.embedded.com/columns/guest/207001013 > >Luminary Micro Announces 32-bit Microcontrollers for $1.00
Okay, but can you get it in an 8-pin package?


Ben Bradley wrote:
> >Guy Macon <http://www.GuyMacon.com/> wrote: > >>While researching something else, I ran into the >>following rather interesting opinions: >> >>Consolidating the MCU market around the ARM architecture >>("It's inevitable. ARM's Cortex-M3 processor core is going >>dominate the MCU market.") >>http://www.embedded.com/columns/guest/207001013 >> >>Luminary Micro Announces 32-bit Microcontrollers for $1.00 > >Okay, but can you get it in an 8-pin package?
Certainly. Just take your wire cutter and snip off 40 of the 48 pins. http://www.luminarymicro.com/products/lm3s811_microcontroller.html IIRC, they also have a 28 pin SOIC version, so you might only have to snip off 20 pins. I hope this helps... -- Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/> Guy Macon <http://www.GuyMacon.com/>
Guy Macon wrote:
> Ben Bradley wrote: >> Guy Macon <http://www.GuyMacon.com/> wrote: >> >>> While researching something else, I ran into the >>> following rather interesting opinions: >>> >>> Consolidating the MCU market around the ARM architecture >>> ("It's inevitable. ARM's Cortex-M3 processor core is going >>> dominate the MCU market.") >>> http://www.embedded.com/columns/guest/207001013 >>> >>> Luminary Micro Announces 32-bit Microcontrollers for $1.00 >> Okay, but can you get it in an 8-pin package? > > Certainly. Just take your wire cutter and snip off 40 > of the 48 pins. > > http://www.luminarymicro.com/products/lm3s811_microcontroller.html > > IIRC, they also have a 28 pin SOIC version, so you might only > have to snip off 20 pins.
> I hope this helps...
And if you choose carefully and cut off the power pins, you should reduce power consumption also, which might be a further help. :-) -- - Stephen Fuld (e-mail address disguised to prevent spam)
Guy Macon wrote:
> Ben Bradley wrote: > >>Guy Macon <http://www.GuyMacon.com/> wrote: >> >> >>>While researching something else, I ran into the >>>following rather interesting opinions: >>> >>>Consolidating the MCU market around the ARM architecture >>>("It's inevitable. ARM's Cortex-M3 processor core is going >>>dominate the MCU market.") >>>http://www.embedded.com/columns/guest/207001013 >>> >>>Luminary Micro Announces 32-bit Microcontrollers for $1.00 >> >>Okay, but can you get it in an 8-pin package? > > > Certainly. Just take your wire cutter and snip off 40 > of the 48 pins. > > http://www.luminarymicro.com/products/lm3s811_microcontroller.html > > IIRC, they also have a 28 pin SOIC version, so you might only > have to snip off 20 pins. > > I hope this helps...
You forgot to mention that such Pin-snip can be legally dangerous!!. So, as well as wearing the appropriate goggles, be sure to do so only in the presence of your lawyer!! For the element of truth to this, see: http://www.microcontroller.com/news/luminary_micro_lawsuit.asp -jg


Jim Granville wrote:
> >Guy Macon <http://www.GuyMacon.com/> wrote: > >> Ben Bradley wrote: >> >>>Guy Macon <http://www.GuyMacon.com/> wrote: >>> >>> >>>>While researching something else, I ran into the >>>>following rather interesting opinions: >>>> >>>>Consolidating the MCU market around the ARM architecture >>>>("It's inevitable. ARM's Cortex-M3 processor core is going >>>>dominate the MCU market.") >>>> >>>>http://www.embedded.com/columns/guest/207001013 >>>> >>>>Luminary Micro Announces 32-bit Microcontrollers for $1.00 >>> >>>Okay, but can you get it in an 8-pin package? >> >> Certainly. Just take your wire cutter and snip off 40 >> of the 48 pins. >> >> http://www.luminarymicro.com/products/lm3s811_microcontroller.html >> >> IIRC, they also have a 28 pin SOIC version, so you might only >> have to snip off 20 pins. >> >> I hope this helps... > >You forgot to mention that such Pin-snip can be >legally dangerous!!. > >So, as well as wearing the appropriate goggles, be sure to >do so only in the presence of your lawyer!! > >For the element of truth to this, see: >http://www.microcontroller.com/news/luminary_micro_lawsuit.asp
There seems to be a lot of that going around... http://www.google.com/search?q=%22Microchip+Technology%22+files+OR+filed+lawsuit -- Guy Macon <http://www.GuyMacon.com/>
"Guy Macon" <http://www.GuyMacon.com/> wrote in message 
news:Vuydne9rWpdwcw_V4p2dnAA@giganews.com...
> There seems to be a lot of that going around... > http://www.google.com/search?q=%22Microchip+Technology%22+files+OR+filed+lawsuit
My impression is that Microchip faltered for a few years inbetween the original line of PICs "maturing" and coming out with dsPICs and other interesting parts. At the time, some core employees left, such as the guys who started up Scenix (later Ubicom -- pipelined 50MHz PICs, essentially), and I recall reading that they mentioned they motivation was due to Microchip management having no interest (at the time) in their ideas. What does a company that no longer has the technical leadership to produce interesting new products do? Sue the guys who do, if it's at all possible that a link can be established between what the new guys are doing and what you were doing back in your heyday, regardless of how tenuous that link might be. I could be completely wrong about this, of course... I just remember those years where it seemed that Microchip had lost its way. ---Joel