irwin@uiucdcs.CS.UIUC.EDU (08/11/86)
I have a question relating to a VAX-780 or 785. What is the zero bit used for in the I/D Register 0C?? On a VMS system it contains 184 584. On a Unix system, it contains 184 584, but sometimes 183 583, in which case, the zero bit contains a "1". Any takers out there on answering this?? Al Irwin Univ of Illinois Dept of Comp Sci Urbana, Il uiucdcs 217-333-4801
chris@umcp-cs.UUCP (Chris Torek) (08/14/86)
In article <30600007@uiucdcs> irwin@uiucdcs.CS.UIUC.EDU writes: >I have a question relating to a VAX-780 or 785. >What is the zero bit used for in the I/D Register 0C?? Register 0C is the SBR (System Base Register). Bits zero and one `MBZ', as DEC puts it in the _VAX Hardware Handbook, 1986_. If you set them, the machine's behaviour is probably `UNPREDICTABLE' (as DEC handbooks like to say). -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 1516) UUCP: seismo!umcp-cs!chris CSNet: chris@umcp-cs ARPA: chris@mimsy.umd.edu