ddb@ns.network.com (David Dyer-Bennet) (10/09/90)
In article <71383@sgi.sgi.com> rpw3@sgi.com (Rob Warnock) writes:
[referring to the DEC PDP-10]
:I don't recall any production software that used 9-bit bytes, though at least
:one attempt at an experimental C compiler used them.
I seem to recall that the COBOL compiler used them for some modes of
character data or character numeric data. Can't figure out why
offhand, though.
--
David Dyer-Bennet, ddb@terrabit.fidonet.org
or ddb@network.com
or ddb@Lynx.MN.Org, ...{amdahl,hpda}!bungia!viper!ddb
or Fidonet 1:282/341.0, (612) 721-8967 9600hst/2400/1200/300parke@star.enet.dec.com (Bill Parke) (10/10/90)
In article <1990Oct8.214604.25320@ns.network.com>, ddb@ns.network.com (David Dyer-Bennet) writes: |> From: ddb@ns.network.com (David Dyer-Bennet) |> Newsgroups: comp.arch |> Subject: PDP-10 (was: Looking for a really odd computer) |> |> In article <71383@sgi.sgi.com> rpw3@sgi.com (Rob Warnock) writes: |> [referring to the DEC PDP-10] |> :I don't recall any production software that used 9-bit bytes, though at least |> :one attempt at an experimental C compiler used them. |> |> I seem to recall that the COBOL compiler used them for some modes of |> character data or character numeric data. Can't figure out why |> offhand, though. At the time, there was a lot of COBOL applications on some other vendors hardware with 4 bytes per word and eight bit encoding. 9 Bits, holds 8 and works, evenly, 4 bytes per 36 bit word. Most ASCII was 5 7 bit bytes, with the bottom bit left over. Setting this bottom bit caused lots of things (SOS, compilers etc) to ignore the "line number" (which just happened to be 5 digits). |> -- |> David Dyer-Bennet, ddb@terrabit.fidonet.org |> or ddb@network.com |> or ddb@Lynx.MN.Org, ...{amdahl,hpda}!bungia!viper!ddb |> or Fidonet 1:282/341.0, (612) 721-8967 9600hst/2400/1200/300 |> -- Bill Parke parke%star.enet.dec@decwrl.dec.com VMS Development decwrl!star.enet.dec.com!parke Digital Equipment Corp parke@star.enet.dec.com 110 Spit Brook Road ZK01-1/F22, Nashua NH 03063 The views expressed are my own.
rick@pavlov.ssctr.bcm.tmc.edu (Richard H. Miller) (10/10/90)
In article <1990Oct8.214604.25320@ns.network.com> ddb@ns.network.com (David Dyer-Bennet) writes: >In article <71383@sgi.sgi.com> rpw3@sgi.com (Rob Warnock) writes: >[referring to the DEC PDP-10] >:I don't recall any production software that used 9-bit bytes, though at least >:one attempt at an experimental C compiler used them. > >I seem to recall that the COBOL compiler used them for some modes of >character data or character numeric data. Can't figure out why >offhand, though. Ah yes....DISPLAY-9. This was also known as EBCDIC. The COBOL compiler would generate IBM compatible programs and would write a tape or read a tape which could be used on an IBM system (32 bit word size, 4 bytes/word). DISPLAY-9 would store 4 characters in a word and when you wrote to the tape, would convert the 36 bit words to 32 bit frames on the tape. Once could select DISPLAY-9 explicitly or one would get it automatically when an IBM recording mode was selected on the FD statement in the data division. It actually worked fairly well, but the programmer had to be very careful that his/her record sizes were an even multiple of both 6 and 4. -- Richard H. Miller Email: rick@bcm.tmc.edu Asst. Dir. for Technical Support Voice: (713)798-3532 Baylor College of Medicine US Mail: One Baylor Plaza, 302H Houston, Texas 77030
an288@cleveland.Freenet.Edu (Mark Hittinger) (03/24/91)
I fiddled with this for a long while after they took my (sniff) KL-10 model A out the door. I'd just managed to get 7.02 to run on it..... Its not ship-able....I wasn't able to get good performance even on the VAX8650. I could probably do better today with some kind of PC card and one of these new MIPS chips. Anybody else fiddling with this? Systems Concepts? I'd need help with the tops-20 pager and writing code to emulate those WEIRDO string instructions like EDIT. I had half decided to just write a KI-10 emulator and tell the 20 people to go away....but.... Could we get tops-10 to run legally? There were two pdp-11 emulators on the 10. -- Mark Hittinger [answering machine (606)-272-2424 PO BOX 43358 Middletown, KY 40243
andrew@alice.att.com (Andrew Hume) (03/27/91)
i have a listing of a fortran program that emulates a pdp11(-20?), a disk and a console interface. it was sufficiently accurate that while running on a honeywell, it booted and ran the V6 distribution tape for Unix. if someone wants to ocr it in.... andrew hume