howto bitsavers BASIC-11 v2 disk image under simh

Fritz Mueller fritzm at
Wed Aug 11 18:06:33 CDT 2021

> On Wed, Aug 11, 2021 at 8:57 AM Fritz Mueller via cctalk
> Could anybody spare a clue or some suggestions on how to access the contents of:

> On Aug 11, 2021, at 1:12 PM, Glen Slick via cctalk <cctalk at> wrote:
> Hmm, maybe that BASIC.DSK image file was created by something that
> only copied the initial allocated logical sectors and ignored unused
> logical sectors at the end of the floppy, and maybe PUTR doesn't
> handle disk image files that are not the expected full size?
> Example of padding the 486,400 byte BASIC.DSK image file to a size of
> 512,512 bytes...[which works]

Ah ha!  Thanks much, Glen!

simh is usually pretty good about padding out attached images, but maybe I'll try the same thing there and see if RT-11 can then read the disk directly itself.  If not, I can extract/rewrite via PUTR.

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