-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 10/29/10 00:04 , Dave Close wrote: > Brandon S Allbery KF8NH wrote: >> I'll add that "octet" is itself something of a leftover from when the 36-bit >> dinosaurs walked the earth. > > That doesn't seem right to me. Certainly 36-bit machines (and 12-bit and > 18-bit ones) frequently divided instruction words into 3-bit units and > used octal notation to represent them. But 36%8 != 0.
The standard convention on PDP10/20 was to split a 36-bit register into 4 9-bit registers; "octet" was largely intended to warn that that wouldn't work well, and the alternative mapping (4 8-bit registers + 4 left over bits) should be used. (fwiw the other common encoding used on those machines was 6 6-bit registers, used with RADIX-50 or SIXBIT.) - -- brandon s. allbery [linux,solaris,freebsd,perl] [email protected] system administrator [openafs,heimdal,too many hats] [email protected] electrical and computer engineering, carnegie mellon university KF8NH -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.10 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkzO/EMACgkQIn7hlCsL25XJlQCgux5d5o34+N+/r7qoeBDRk7C4 8kIAnAwFRVvEmtD2smDoSrRq3R7oWy9M =4QSn -----END PGP SIGNATURE----- _______________________________________________ Tech mailing list [email protected] http://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
