yadran@ucla-cs.UUCP (02/01/85)
I'm trying to use the vax-11' compatibility mode on an object code written for
a pdp-11/45 computer, and getting the message "file compiled with separate i/d
space".
Is there anybody out there who knows about the compatibility mode and the
meaning of that message?
What should I do about it?
Where can I get good information about the compatibility mode?
Thanks,
Yadranguy@rlgvax.UUCP (Guy Harris) (02/05/85)
> I'm trying to use the vax-11' compatibility mode on an object code written for > a pdp-11/45 computer, and getting the message "file compiled with separate i/d > space". > Is there anybody out there who knows about the compatibility mode and the > meaning of that message? The meaning of the message is that PDP-11 compatibility mode doesn't support separate I/D space. (Heck, says DEC, none of *our* software uses it - well, RSX-11M+ does, but it didn't exist when they did the 780). > What should I do about it? Find a PDP-11 to run your program on (the microVAX doesn't have compatibility mode either - I have no idea whether DEC plans to support it indefinitely or not). > Where can I get good information about the compatibility mode? Get a copy of the VAX-11 Architecture Reference Manual (EK-VAXAR-RM-001) from your local DEC office. (List of things not supported in compatibility mode, from that manual: Privileged instructions "Special instructions" such as traps and WAIT (well, EMT and TRAP work, since PDP-11 programs can make system calls both under VMS and UNIX compatibility modes) Access to internal processor registers (i.e., referencing them with addresses like 0177776 for the PSW) Direct access to trap and interrupt vectors Direct access to I/O devices Interrupt servicing Stack overflow protection Alternate general register sets Any processor mode other than user and separate I and D spaces Floating point instructions) Guy Harris {seismo,ihnp4,allegra}!rlgvax!guy > > Thanks, > Yadran *** REPLACE THIS LINE WITH YOUR MESSAGE ***
henry@utzoo.UUCP (Henry Spencer) (02/10/85)
Actually, a friend who got one of the first 780's outside DEC, and had
DEC people working with them for a while getting it running, mentioned
one other thing that compatibility mode doesn't support: the MARK
instruction. This omission is (I believe) undocumented, but it's not
surprising that nobody has noticed the absence of the most useless
instruction ever added to the 11...
--
Henry Spencer @ U of Toronto Zoology
{allegra,ihnp4,linus,decvax}!utzoo!henry