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From: Richard Maine on 8 Aug 2010 09:48 Terence <tbwright(a)cantv.net> wrote: > My compiler for this job is MS 3.31 of August 1985. Checked manual > index; nor reference to ENTRY, which I have used somewhere else in the > past; bit surprised! That probably explains it. I wasn't sure that you were still using that compiler, but if I recall correctly, it was one of the very few f77 subset compilers ever made. I used to think it was the only one, but someone did mention one or maybe two others. > Not in Burroughs, or IBM Fortran manuals of same > date that I have, either. Probably f66 compiler manuals. IBM was quite late in releasing their f77. I forget the exact date. I think it was before 1985, but I know it was late, and it is plausible that you still had f66 compiler manuals even after they had released an f77. I recall that people at IBM were determined not to be so embarassingly late with an f90 compiler as they had been with f77. I couldn't say about Burroughs. I did use Fortran on a Burroughs machine a bit, but it was well before f77. Heck, that would have been about 1968 and might have been before they had an f66. -- Richard Maine | Good judgment comes from experience; email: last name at domain . net | experience comes from bad judgment. domain: summertriangle | -- Mark Twain
From: Nick Maclaren on 8 Aug 2010 10:11 In article <1jmw7tr.1avukv1tpt21eN%nospam(a)see.signature>, Richard Maine <nospam(a)see.signature> wrote: >Terence <tbwright(a)cantv.net> wrote: > >> Not in Burroughs, or IBM Fortran manuals of same >> date that I have, either. > >Probably f66 compiler manuals. IBM was quite late in releasing their >f77. I forget the exact date. I think it was before 1985, but I know it >was late, and it is plausible that you still had f66 compiler manuals >even after they had released an f77. I recall that people at IBM were >determined not to be so embarassingly late with an f90 compiler as they >had been with f77. They decided, originally, that nobody was interested in Fortran 77, and still had the delusion that PL/I would take over the world. They were then forced to write a Fortran 77 compiler for a procurement, wrote a joke one, and were amazed at how many sold. They then had no end of trouble turning it into a real product. It would have been easier to start from scratch, but you know how bureaucracies work. I might have enough documentation to identify the date at work, but probably not. Regards, Nick Maclaren.
From: Richard Maine on 8 Aug 2010 10:08 Terence <tbwright(a)cantv.net> wrote: > Am I correct in thinking this first use sets LCM to 120000 bytes (a > CDC use of Fortran) or would this be 120000 BITS? It cannot be a bit > value because of that "2". > LCM=120000B Variable values aren't bytes, bits, or any units. They are just numbers. At least that is so in Fortran (and almost all computer languages). The programmer's intent can be for those numbers to represent numbers of some unit, but you won't find that in the language syntax. Numbers in Fortran have a base, but not units. Binary and hex would be bases. Bits and bytes are units. I think I detect a confusion between the two. CDC machines of that era did not have bytes. At all. Somewhat oddly, the B in this syntax on a CDC indicates octal. It is just my speculation, but I suppose that they (correctly) figured that using the letter O for such a thing would be prone to being misread as a digit 0. I also think there was a bit of a notion that octal was just sort of a shorter notation for a value that one might think of as binary. It is so trivial to translate octal to binary in one's head that I think casual terminology sometimes blurred the difference. If this represents something about memory (as is plausible - the CM in LCM might stand for core memory), the units are probably 60-bit words. That's the units that memory was measured in. As noted previously, characters were 6 bits, but the machine could not physically address individual characters and there wasn't really a term used to refer to the storage used by a character. On occasion, you might here someone talking about the machines having a 6-bit byte, but I don't consider that accurate; they just didn't have bytes of any size - only words. -- Richard Maine | Good judgment comes from experience; email: last name at domain . net | experience comes from bad judgment. domain: summertriangle | -- Mark Twain
From: Nick Maclaren on 8 Aug 2010 10:21 In article <1jmw8bk.11rn30t1asz51cN%nospam(a)see.signature>, Richard Maine <nospam(a)see.signature> wrote: > >If this represents something about memory (as is plausible - the CM in >LCM might stand for core memory), the units are probably 60-bit words. >That's the units that memory was measured in. As noted previously, >characters were 6 bits, but the machine could not physically address >individual characters and there wasn't really a term used to refer to >the storage used by a character. On occasion, you might here someone >talking about the machines having a 6-bit byte, but I don't consider >that accurate; they just didn't have bytes of any size - only words. On the ICL 1900, there were a few instructions to address individual characters - using the top 2 bits to index within the 24-bit word! It had three character sets, of course :-) Regards, Nick Maclaren.
From: mecej4 on 8 Aug 2010 10:52
Richard Maine wrote: > Terence <tbwright(a)cantv.net> wrote: > >> My compiler for this job is MS 3.31 of August 1985. Checked manual >> index; nor reference to ENTRY, which I have used somewhere else in the >> past; bit surprised! > <--CUT--> >> Not in Burroughs, or IBM Fortran manuals of same >> date that I have, either. > > Probably f66 compiler manuals. IBM was quite late in releasing their > f77. I forget the exact date. I think it was before 1985, but I know it > was late, and it is plausible that you still had f66 compiler manuals > even after they had released an f77. I recall that people at IBM were > determined not to be so embarassingly late with an f90 compiler as they > had been with f77. I have a copy of IBM GC26-3986-1, Release 1.1, the 2nd. edition, January 1982, VS FORTRAN, Application Programming: Language Reference. The preface says "... includes full ANS FORTRAN plus IBM extensions". ENTRY is definitely there, and is covered in pages 81-83. -- mecej4 |