16 votes
Accepted

What did Richard Stallman have against VMS?

I have access to the file RMS; VMS 7 dated 1980-07-12. I can't make it public, but I can read it and I believe it's ok for me to paraphrase and summarize it. RMS argues VMS lacks several important ...
Lars Brinkhoff's user avatar
14 votes
Accepted

Did VMS ever acquire filesystem cross-links?

Even ODS-1 on RSX-11D and RSX-11M, ancestors of VMS running on the PDP-11, could have cross-links, but you wouldn't want to. What made this possible was the separation of low-level APIs for file ...
dave's user avatar
  • 35.6k
13 votes

Were the VAX eXtended Function Control (XFC) instructions ever used commercially?

I was VAX Architect for six years in the late '80s, and at least during my tenure, Raytheon was the only company licensed to design VAX-compatible processors, for producing MIL-SPEC machines. They did ...
Tim Leonard's user avatar
10 votes

Did VMS ever acquire filesystem cross-links?

OpenVMS added support for hard links in ODS-5 volumes with hard links enabled, in version 7.2 (released in February 1999, long after Dave Cutler’s departure). This is older than proper support for ...
Stephen Kitt's user avatar
10 votes
Accepted

Why did the VAX compatibility mode not implement the MARK instruction?

A valid reason is: why bother implementing something in hardware if it is very rare (perhaps only appearing in a bunch of very old executables compiled from Fortran or Pascal), and can be implemented ...
Leo B.'s user avatar
  • 19.1k
9 votes

Mainframe Hater's Handbook?

"The Unix-Haters Handbook" is a product of a particular time and place that made an entire book possible, the rise of RISC workstations and the Internet. People had been grumbling about ...
Hugh Fisher's user avatar
8 votes

Porting of software from the m68k family architecture to the DEC VAX

I can give you an anecotal answer. I did this a few times. I suspect that porting in this direction would have been unusual. We only did it where the customer insisted on the use of Vax hardware. ...
Chenmunka's user avatar
  • 8,141
8 votes
Accepted

VAX 11/780 16MB memory board - what was the physical size?

In answering this question, I found that there were multiple generations of 11/780 memory board, and so sizes, capacity, etc., are quite hard to pin down. I still have not found a board larger than ...
dave's user avatar
  • 35.6k
8 votes
Accepted

DEC "CI" bus, better known as?

At a certain point in the 1980s, 'I' things were all the rage in DEC. BI - Backplane Interconnect (the bus in the 8xxx series VAXen - see Wikipedia) CI - Computer Interconnect (showed up as star ...
dave's user avatar
  • 35.6k
5 votes

Were the VAX eXtended Function Control (XFC) instructions ever used commercially?

I microcoded up all the UNIX string functions, just to see if anything could be gained; and also a dynamic programming solution of an esoteric parsing problem. The former would need huge strings to ...
rhhardin's user avatar
5 votes

VAX 11/780 16MB memory board - what was the physical size?

This is a VAX module but likely for an 11/780 successor, not an 11/780. The edge connector with approximately 150 signals per side and the ECL flip flops with 1987 date codes suggest that we are ...
Eli Rosenberg's user avatar
5 votes

What did Richard Stallman have against VMS?

A Google search turned up no sign of that file. I'd be surprised if a search would turn up anything as RMS;VMS indicates a local file on his account on a machine called MIT-AI. Likewise a reply to ...
Raffzahn's user avatar
  • 223k
5 votes
Accepted

What random number generator was used in the VAX game Empire?

From the DECUS VMS Fortran source, the random routine RND() is as follows: FUNCTION RND(IHIGH) C IMPLICIT INTEGER(A-Z) INTEGER*2 TIME(4) EQUIVALENCE (TIME(2),SEED) REAL MTH$RANDOM ...
scruss's user avatar
  • 21.6k
4 votes
Accepted

Why did it take 2 hours to switch to a standby VAX?

I wasn't there, so I don't know why it took two hours. If I had to invent a plausible scenario, it would be along these lines. The VAX is a transaction processor with a database that reflects the ...
Walter Mitty's user avatar
  • 6,128
3 votes

VAX 11/780 16MB memory board - what was the physical size?

Other responders have already given the exact size from data sheets, but it's also possible to get a good estimate of the size of a thing from the size of its parts. This is a useful skill when we ...
pndc's user avatar
  • 11.3k
3 votes

VAX 11/780 16MB memory board - what was the physical size?

To give you a sense of the inter-board spacing in these types of systems, it is useful to consider the main constraints. These include airflow for cooling, the physical space between the connectors on ...
Shaheed Haque's user avatar
3 votes

Were the VAX eXtended Function Control (XFC) instructions ever used commercially?

There was a user guide for the VAX-11/780 microprogramming tools with an example of how to create and invoke user-written microcode. See https://stackoverflow.com/questions/6390036/vax-what-cpus-can-...
Aron Insinga's user avatar
2 votes

Why did the VAX compatibility mode not implement the MARK instruction?

One plausible explanation is the MARK instruction was not implemented on all PDP-11 processors therefore a architectual design decision was made not to implement the MARK instruction. This is ...
PDP11's user avatar
  • 710

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