Imaging RX02 disks for simh (was: Re: MU-BASIC V2 and RT-11 V03B distribution disks.)

Brian Walenz thebri at
Sun Mar 6 10:56:31 CST 2016

How the heck do you copy an RX02 disk for use in simh?

I've been trying to transfer RX02 images between simh and a real PDP11
(that has only two RX02's, console, and ethernet).  So far, I've only
attempted sending an RX02 image from the PDP to simh, but simh fails to
read it: "?DIR-F-Invalid directory".  Even after adding 13*512 bytes to the
start for the missing track, I still get invalid directory.

then FTP that off the PDP, delete the file, and do the remaining two thirds
of the disk.  Once all are transferred, "cat *DAT > floppy.dsk".

I can transfer RX50 images using the same recipe, though I haven't tried
sending an RX50 image created on simh back to the PDP.

For what it's worth, I'm having the same problem with Alan Baldwin's TCP/IP
disk images from  simh can't read the
individual DSK images, but could read the *.PKG with the disks inside, and
from that, I could (RT-11) MOUNT each disk to a logical device.


On Thu, Jan 28, 2016 at 11:50 AM, Mattis Lind <mattislind at> wrote:

> I found some 8 inch floppies with distribution kits for MU-BASIC V2 and
> RT-11 V03B. I imaged those and put them here
> if anyone is interested in playing with MU-BASIC. There are both RAW disk
> images and to be used in SimH and like and also DMK/IMD files.
> The system that floppies came with is this little (
> )
> system once used at Scania in Södertälje.

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