On 12/3/19 11:00 PM, Lamar Owen wrote: Well, glad it helped. And here's more... I have succeeded in getting RSX-180 installed on a hard disk. In doing so I have learned some things that others might consider valuable as well. Disk sizes and formats are more important than one might realize Oversized hard disk partitions cause really strange behavior totally unrelated to disk I/O. When I tried to use a disk partition that was too big the system merely spewed garbage to the screen. But the second lesson is even more important. The Support Page states: "For best performance format the floppy first under CP/M, so the sectors will have the optimum interleave value for the P112 hardware. Otherwise, disk accesses will be very slow." This is not accurate. When I used a brand new pre-formatted floppy without formatting it under CP/M it booted but many of the commands failed to work and even th4e directory could not be seen. Formatting on CP/M and then using rawrite to place the image on the floppy fixed that. I have been having a problem getting CP/M 3 to boot and now suspect it may be the same problem. Again, I used a pre-formatted brand new floppy and rawrite. When I try to boot it starts loading and then spews what looks like random garbage to the screen. I am going to try using a CP/M formatted floppy and I actually expect it will fix the problem. bill