This add-on the SIMH simulator allows you to attach a file as a ROM image and boot the simulator via the ROM. The ROM images listed below can be used to boot SIMH.
I have two different versions of the KDF11B boot roms available for download. These files are binary images of the roms. You will have to split the file into even and odd bytes to burn into two different roms. The even bytes should be burned into a rom and placed in socket E126. The odd bytes should be burned into a different rom and placed in socket E127.
There is an unresolved problem with using these images and under the SIMH Simulator. However the BDV11 images does work correctly. The root cause of the problem lies in the fact that not all PDP11s behave exactly alike and the boot roms were written to run on an 11/23 (F-11), not an 11/73 (J-11). One identified issue is the illegal instruction trap. The ROMS expect an illegal instruction trap to vector through address 4, but simh vectors through 010 (which is the behavior of an 11/73.)
You can also burn these images into smaller roms and install them on a real BDV11. This will add MSCP and TMSCP boot support to these older systems. This will only work with F-11 processors however.
See the Firmware Readme for the prom checksums and the post installation verification procedure.
This ROM image corresponds to DEC part numbers 23-339E2-00 and 23-340E2-00. This is the standard image on BDV11s and some of the older 11/23+ boards.
When using this image with the BDV11 add-on to SIMH, set BDV0's Option Select Register (OSR) to allow interactive booting.
d bdv0 OSR 7773
Chuck McManis has put the latest versions of the RQDX3 firmware on his site. This firmware is necessary if you want to format RDnn disks. Click here to visit his site.