another bizarre architecture
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From: John Devereux on 31 Jan 2007 16:50 John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> writes: > This looks really weird to me... > > http://www.maxim-ic.com/appnotes.cfm/appnote_number/3960 > > Does it resemble anything you've ever seen? Its been out for a while now - I don't see advantage over more established cores like MSP430 and ARM. And lots of disadvantages. > It looks truly ghastly to > program. For example, allowing printf() to use floats adds 3500 bytes > to a program binary. Then don't do that! The full printf is quite powerful (and complicated internally). An integer-only version can be made quite compact and is still quite powerful. If you are determined to use floating point you can pass the integer and fractional parts as separate parameters to the function, using a format string that combines them visually. -- John Devereux
From: Spehro Pefhany on 31 Jan 2007 19:56 On Wed, 31 Jan 2007 19:49:58 GMT, the renowned Rich Grise <rich(a)example.net> wrote: >On Wed, 31 Jan 2007 11:03:03 -0800, John Larkin wrote: > >> This looks really weird to me... >> >> http://www.maxim-ic.com/appnotes.cfm/appnote_number/3960 >> >> Does it resemble anything you've ever seen? It looks truly ghastly to >> program. For example, allowing printf() to use floats adds 3500 bytes >> to a program binary. >> > >Yes, it does resemble something I've seen - microcode. ;-) It actually >looks like something I'd enjoy playing with. :-) > >And yes, I'd expect a printf() to use that many bytes - printf() is a >freakin' monstrosity in any case. What does puts() compile to? It is extremely simple. http://www.koders.com/c/fid61148695142D20F84C4E83E059EEED5677E7CD79.aspx >I'd think >it wouldn't take a very big loop to turn a float into a string. Don't be a puts(). You have to convert binary to ASCII, denormalize, deal with leading and trailing zeros, decimal points, and so on. >Cheers! >Rich > Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff(a)interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
From: John Larkin on 31 Jan 2007 20:04 On Wed, 31 Jan 2007 19:56:21 -0500, Spehro Pefhany <speffSNIP(a)interlogDOTyou.knowwhat> wrote: >On Wed, 31 Jan 2007 19:49:58 GMT, the renowned Rich Grise ><rich(a)example.net> wrote: > >>On Wed, 31 Jan 2007 11:03:03 -0800, John Larkin wrote: >> >>> This looks really weird to me... >>> >>> http://www.maxim-ic.com/appnotes.cfm/appnote_number/3960 >>> >>> Does it resemble anything you've ever seen? It looks truly ghastly to >>> program. For example, allowing printf() to use floats adds 3500 bytes >>> to a program binary. >>> >> >>Yes, it does resemble something I've seen - microcode. ;-) It actually >>looks like something I'd enjoy playing with. :-) >> >>And yes, I'd expect a printf() to use that many bytes - printf() is a >>freakin' monstrosity in any case. What does puts() compile to? > >It is extremely simple. >http://www.koders.com/c/fid61148695142D20F84C4E83E059EEED5677E7CD79.aspx Monkeys with typewriters. Most of the functions say nothing about what they do, and many are effectively or entirely comment-free. This is the Microsoft philosophy: the only documentation is the code itself. > >>I'd think >>it wouldn't take a very big loop to turn a float into a string. > >Don't be a puts(). You have to convert binary to ASCII, denormalize, >deal with leading and trailing zeros, decimal points, and so on. Fixed-point 64-bit to formatted ascii string is maybe a page of assembly for the 68K. Might run over a page with zero supression and commas every 3 digits. John
From: larwe on 31 Jan 2007 20:51 On Jan 31, 2:47 pm, Mike Harrison <m...(a)whitewing.co.uk> wrote: > >wise. We have a lot of investment in ARM, AVR and MSP430; MAXQ is just > >"yet another proprietary microcontroller" with no really compelling > > And it's from Maxim.... usually a distinct disadvantage, availabilitywise The company I work for is big enough (and Maxim is desperate enough) that Maxim would make a supply shortage someone else's problem, not ours - as long as the foundry was physically operational :) But I hear you. The problem is, all vendors are the same. Vendor A screws up five things in a row and goes on the "design 'em out!" shitlist. Vendor B comes in with replacement products, and all is sweetness and light. Three years later, Vendor B screws up five things in a row and goes on the "design 'em out!" shitlist. Vendor C comes in with replacement products, and all is sweetness and light... { ... } ... repeat until you run out of vendors and then Vendor A comes in with replacement products, Purchasing kisses and makes up with their rep, and all is sweetness and light... .... for another three years.
From: Alex Colvin on 31 Jan 2007 23:19
>http://www.maxim-ic.com/appnotes.cfm/appnote_number/3960 >Does it resemble anything you've ever seen? It looks truly ghastly to >program. For example, allowing printf() to use floats adds 3500 bytes >to a program binary. I used to work with New England Digital (no relation to DEC) Able computers. The first commercial single-instruction computer. Built out of MSI circuitry and used as a signal processor in the first commercial digital synthesizers. http://world.std.com/~alexc/able.html One of these days I'd love to do it in VHDL, although I bet Cameron already has. -- mac the na�f |