Hi Joe, I've found some other docs that confirm this. When I catalog the drive with a device that only supports CS80 (my HP 3562A Spectrum analyser) I see only one file (called SYSTEM_SA). When I attach the drive to an HP 9000 332 CPU, it finds the SYSTEM_SA file and then displays something like 'Secondary loader v 56.6' - I assume that this is the part that provides support for HFS. Once the secondary loader has done its stuff the 9000 332 will catalog the drive as usual and displays HFS as the filesystem. <snip> Ignore my comments on this - my mistake. The numbers come from the 'Identify' CS80 command that is used at power on by the system controller to identify devices attached to the HPIB bus. The values 1 and 15 are consistent with the 9134x <snip> I should have been more specific - the drive that fails is the 9134x - it fails because it is an amigo drive not a CS80. <snip> Thanks for the info Joe. I need to explain this one more fully! The HP 7907 is a 20.5MB (fixed) + 20.5MB (removable) HPIB controlled disk drive. The removable cartridge is a 9 inch by 9 inch by 1 inch box containing a single 8 inch platter. The drive wieghs about 60 lbs - it comes in the same width box as an HP 9000 300. It looks as though the removable portion of the drive is primarily for backup as separate panel controls are provided for Fixed->Removable and Removable-> fixed. I have one of these - I've just been using it for testing the CS80 / LIF reader software that I've been writing. The HP 7906 is a 5 MB (fixed) + (5 MB) (removable) (I think) MAC controlled HDD. I have one attached to my 5451C Fourier Analyser. It uses a 13037 interface card in the HP 1000 computer plus an external controller marked 13037A. I think that the controller can control up to 8 drives at once. The removable cartridge is around 17 inches in diameter. The drive weighs a lot - it takes two people to lift. My problem is that I have software on 7906 removable cartridges that I need to back-up. If I can find an HPIB controlled version of the 7906 then I may be able to support it with the HPIB reader software. Do you have any more information about the 12745C/D MAC to HPIB converter? - this sounds as though it will do the job! I've down-loaded the command set documentation that Frank has scanned etc. It looks as though it may be what I'm looking for re. amigo command set. Interestingly the docs themselves do not seem to use the word amigo anywhere?? As usual Joe, many thanks for taking the time to look this stuff up! - hopefully we should all end up with an application that will let us back-up and share our age-ing software. Do you have any info on how HFS works? Cheers Peter Brown _________________________________________________________________ It's fast, it's easy and it's free. Get MSN Messenger today! http://www.msn.co.uk/messenger