Reply by Richard Henry February 28, 20052005-02-28
"Grant Edwards" <grante@visi.com> wrote in message
news:4220b07d$0$46587$a1866201@visi.com...
> On 2005-02-26, Kelly Hall <khall@acm.org> wrote:
> > RS-232. > > I've no complaints about RS-232. I've seen it misused and > poorly implimented over the years, but I don't see anything > wrong with the standard.
What do you think the standard says?
Reply by February 27, 20052005-02-27
> I've done a bit of '85->'86 translation. No, I didn't have a > 'tool' to do it. I did 90% of it with Brief key-stroke macros. > The result was like German->English using only a dictionary and > not changing the grammar, but it did work and was a fast, accurate
I've just recently finished a project very like this - translating from COP8 to NEC 78K0 using a pure algorithmic translation method. It worked amazingly well; I was very surprised.
Reply by Bob McConnell February 27, 20052005-02-27
On 26 Feb 2005 23:52:30 GMT, Grant Edwards <grante@visi.com> wrote:

>On 2005-02-26, Elder Costa <elder.costa@terra.com.br> wrote: > >> It's been a long time since I last designed with and >> programmed a PIC (in Assembly) but I will comment on it all >> the same. AFAIK the PIC was derived from an IBM peripheral >> controller (IIRC PIC stands for peripheral intelligent >> controller) > >I think it was actually Peripheral Interface Controller. >
IIRC, Intel's part was called the Programmable Interrupt Controller. It was basically a dedicated function 8 bit controller. My 8085 books are all in storage or I would look it up. Bob McConnell N2SPP
Reply by Albert van der Horst February 27, 20052005-02-27
In article <opsmnukld2y1ubid@news>,
Vadim Borshchev  <vadim.borshchev@127.0.0.1> wrote:
>On Wed, 23 Feb 2005 17:27:55 +0100, Mouarf <mouarf@chezmoi.fr> wrote: > >> I'm not sure, see the PXA processor from Intel that use ARM >> architecture........ > >Absolutely. PXA is based on XScale (micro)architecture, which is in turn >"ARM Architecture 5TE", by ARM nomenclature. > >Your original question was about x86, which is completely different can of >worms. It all has started the day Intel decided to ..ermm.. "extend" >their i8080 processor and make it 16-bit. The new i8086 processor had >inherited the odd registers functionality and names. Subsequent family >members (286, 386, 486, 586 aka Pentium, 686 aka PentiumII) just added to >the mess. Due to the numbering convention this whole line is referred to >as "x86".
I have the original introduction by Morse the designer of the 8086. He is somewhat critical of his own design and Intels assembler, too. I think the 8086 is a decent processor, and a feat of upwards compatibility. But it really should have been the end of it. Extending the lifetime of the processor from 16 bits to 20 bits addressing, counting for 4 years in computer history, and there it should have stopped. The real mess didn't start until the addition of protected mode. Even so, some Unix clones (notably Coherent) show that there was a way out. But Microsoft killed the attempts of IBM to get out of the BIOS morass (microchannel) and forced Intel to introduce the "virtual real mode". Even so Linux proves that if you ignore sufficient of its features the Intel 386 is a decent processor. A great deal of the mess in a Linux system has to do with the battle for the control of the boot code waged by Microsoft (BIOS).
>As Intel produces Itanium (or do they still?), the "x86" get another name, >"IA32". Itanium, for it's 64-bit nature, is named "IA64". > >And now ask somebody about i8035 or i8051 :)
8051 another dead-ugly processor ... But I prefer them over the PIC's.
> > >HTH, > Vadim
-- -- Albert van der Horst,Oranjestr 8,3511 RA UTRECHT,THE NETHERLANDS One man-hour to invent, One man-week to implement, One lawyer-year to patent.
Reply by Paul Keinanen February 26, 20052005-02-26
On 26 Feb 2005 20:54:26 +0100, rob@rupert.sysgo.com (Robert Kaiser)
wrote:

> >> RS-232. > >And whats wrong with this?
While the RS-232 "standard" may be adequate for the initial purpose of connecting a serial signal from a computer (DTE) to a modem (DCE) in an adjacent rack, the worst problems with RS-232 for any general purpose interface is the far too high impedance levels compared to any realistic cable characteristic impedance and the problem with ground potential differences, since no galvanic isolation is required. Paul
Reply by Grant Edwards February 26, 20052005-02-26
On 2005-02-26, Elder Costa <elder.costa@terra.com.br> wrote:

> It's been a long time since I last designed with and > programmed a PIC (in Assembly) but I will comment on it all > the same. AFAIK the PIC was derived from an IBM peripheral > controller (IIRC PIC stands for peripheral intelligent > controller)
I think it was actually Peripheral Interface Controller.
> and it was meant to provide an additinal (yet minimal) level > of intelligence, flexibility and compactness where usually > plain logic would do fine.
I don't think it was IBM, but the rest is mostly right. General Instrucments adapted the PIC from a Signetics design back in the 70's to handle I/O related tasks for some other long since extinct processor. I think originally it came from Harvard or somewhere.
> I think the problem with PICs is Microchip simply extended it > far beyond the original architecture could stand and so they > ended with a jurry rigged solution. Just as with 8x51. For > that matter the x86 architecture suffers the same problem in > order to support legacy applications.
Well put. The PIC, the 8051, and the IA32 have all suffered from the universal hammer syndrome. -- Grant Edwards grante Yow! Yow! Those people at look exactly like Donnie visi.com and Marie Osmond!!
Reply by Elder Costa February 26, 20052005-02-26
Grant Edwards wrote:
> The PIC does seem like a bit of mess > > >>8051. > > > When the 8051 was introduced, it was damned elegent. > > Everybody I knew loved it. > > Since then, people have taken it and tried to use it in some > very inappropriate (IMO) situations. For example, the > architecture simply wasn't intended to deal with more than 64K > of code, with external RAM, or with a stack-intensive language > like C. Sure there are kludges you can use to do those sorts > of things, but it's not pretty. >
It's been a long time since I last designed with and programmed a PIC (in Assembly) but I will comment on it all the same. AFAIK the PIC was derived from an IBM peripheral controller (IIRC PIC stands for peripheral intelligent controller) and it was meant to provide an additinal (yet minimal) level of intelligence, flexibility and compactness where usually plain logic would do fine. I think the problem with PICs is Microchip simply extended it far beyond the original architecture could stand and so they ended with a jurry rigged solution. Just as with 8x51. For that matter the x86 architecture suffers the same problem in order to support legacy applications. Just my EU0.02.
Reply by February 26, 20052005-02-26
On Saturday, in article <8cSdnUye0uqibL3fRVn-hg@omsoft.com>
     jstewart@jkmicro.com "Jim Stewart" wrote:
>Robert Kaiser wrote: >> In article <vUYTd.945$C47.661@newssvr14.news.prodigy.com>, >> Kelly Hall <khall@acm.org> writes: >>>Robert Kaiser wrote: >>> >>>>So, apparently, technical elegance does sometimes pay, *especially* >>>>in the embedded market. >>>
...
>>> Forth. >> >> >> What with Forth wrong is? Strange UPN you may find, but else? >> >> >>> RS-232. >> >> >> And whats wrong with this? >> >It's hard to name anything that's right >with it. Swinging several volts from >a positive rail to a negative rail to >transmit at a low symbol rate for a few >meters...
Having seen the standard being used to transmit down a couple of kilometres, obviously I am wrong. Unless of course you are referring to the MIS-interpreted 12-15m distance quote about noise.
>The 'standard' involved a DB-25 connector >with about a dozen signals, which everyone >implemented differently...
RS232 did NOT specify the conncetor until RS232-C onwards. The DB-25 connector was a PTT standard (CCITT later ITU-T) specification for modems, hence the DTE/DCE specifications. Also the synchronous/asynchronous for 300baud to leased line specifications. RS232 did not specify things like DTR/DSR or CD/RI that was the modem specifications hence NULL modem cables.
>How many manhours has been wasted dicking >around with serial cables?
Mainly by those who did not understand the standard and grabbed any old cable. -- Paul Carpenter | paul@pcserviceselectronics.co.uk <http://www.pcserviceselectronics.co.uk/> PC Services <http://www.gnuh8.org.uk/> GNU H8 & mailing list info <http://www.badweb.org.uk/> For those web sites you hate
Reply by Jim Stewart February 26, 20052005-02-26
Robert Kaiser wrote:
> In article <vUYTd.945$C47.661@newssvr14.news.prodigy.com>, > Kelly Hall <khall@acm.org> writes: > >>Robert Kaiser wrote: >> >>>So, apparently, technical elegance does sometimes pay, *especially* >>>in the embedded market. >> >>PIC. 8051. Z8. > > > I wouldn't know, never used any of these. > > >> Forth. > > > What with Forth wrong is? Strange UPN you may find, but else? > > >> RS-232. > > > And whats wrong with this? >
It's hard to name anything that's right with it. Swinging several volts from a positive rail to a negative rail to transmit at a low symbol rate for a few meters... The 'standard' involved a DB-25 connector with about a dozen signals, which everyone implemented differently... How many manhours has been wasted dicking around with serial cables?
Reply by Robert Kaiser February 26, 20052005-02-26
In article <vUYTd.945$C47.661@newssvr14.news.prodigy.com>,
	Kelly Hall <khall@acm.org> writes:
> Robert Kaiser wrote: >> So, apparently, technical elegance does sometimes pay, *especially* >> in the embedded market. > PIC. 8051. Z8.
I wouldn't know, never used any of these.
> Forth.
What with Forth wrong is? Strange UPN you may find, but else?
> RS-232.
And whats wrong with this? Rob -- Robert Kaiser email: rkaiser AT sysgo DOT com SYSGO AG http://www.elinos.com Klein-Winternheim / Germany http://www.sysgo.com