PDP-11 disk image question

J. David Bryan jdbryan at acm.org
Sat Feb 16 19:24:28 CST 2019


On 2/16/19 7:55 AM, Bill Gunshannon via cctalk wrote:

> So, I used SIMH to do an install of a complete OS on an RA81 disk.  I
> would like to  move this to a real disk and try it on a real PDP-11.

Note that SIMH always writes disc images in little-endian format, 
regardless of host platform.  If your real PDP-11 expects to see big-endian 
16-bit words coming from the drive, you'll need to byte-swap the disc image 
before writing it to a real disc.

(This is necessary, e.g., when copying an HP 1000 disc image generated by 
SIMH to a real HP disc drive.)

                                      -- Dave



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