Posted Feb 23, 2007 18:57 UTC (Fri) by AJWM
Parent article: How an Accident of Hardware Design Encouraged Open Source (O'ReillyNet)
The article makes a big deal out of the byte ordering differences between IBM's 360/370 series and DEC's PDP-11 series (both of which used an 8-bit byte).
It had nothing to do with byte order. It had everything to do with the fact that the IBM used EBCDIC as its native character set, which among its other faults, is non-contiguous in its alphabetic sequences. That's what makes text manipulation such a pain in the butt on those systems. The article doesn't even mention EBCDIC.
(Mind, that's more an OS limitation than hardware -- Amdahls Unix V7 for the 370 architecture, UTS, used ASCII, and porting apps from a PDP-11 to a 370 running UTS was trivial.)
A contemporary major line of systems, Burroughs', used a 48-bit word and strings of either 6-bit characters (common on many architectures, hence the lack of lower case letters) or 8-bit, the latter either EBCDIC or ASCII. The systems had dedicated string processing hardware, the segment descriptor that pointed to the string specified the character set.
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