I'm not Joe, but I can answer this. Off the shelf, from Intel, CP/M-80 did support the bubble memory as a storage device. Also, the Intel operating system called ISIS-PDS did support up to two of the iSBX-251 modules as :F4: and :F5: (ISIS called its drives :Fn: rather than letters like cp/m). I have never used the CP/M os with bubble memory as storage, but I have used a rather interesting configuration. I made the bubble device a bootable device. The PDS will ask you if you want to boot from the bubble if there is no bootable diskette in the drive. I answer yes, and the processor A boot ISIS from the bubble. Then I put a cp/m disk into the drive, close the door, and tell the other processor (when the optional second processor board is installed) "No", don't boot way I have two processors each running a different os. I just have to keep track which processor I tell to access which logical drive, so ISIS doesn't try to access a CP/M disk and vice versa. It sounds like we have a few iPDS owners here on the list who would like the iSBX add-on board. Sure would be nice to find some. I have one, and that one is being used. I'm putting some documentation together for the iPDS into pdf files, some executables, and some one-of-a-kind listings and custom coding. Where might be a good place to host it so that others can download it as needed? Dave Innfogra(a)aol.com wrote: