I've been playing with Apple IIgs SCSI drives in MAME .209 and they work great. I can get both cd-roms and hard-drives mounted and functioning together. And I can boot from a cd-rom on its own.

But when I try to boot directly off a SCSI hard-drive with no cd-rom, the IIgs hangs for about 60 seconds before starting to boot, after which it's all good.

So this command works:

mame64 apple2gs -sl7 scsi -hard1 D:\Mame\software\apple2gs\SCSIHD.chd -sl7 scsi -cdrom1 D:\Mame\software\apple2gs\cd.iso

And so does this:

mame64 apple2gs -sl7 scsi -cdrom1 D:\Mame\software\apple2gs\cd.iso

But this results in a temporary hang:

mame64 apple2gs -sl7 scsi -hard1 D:\Mame\software\apple2gs\SCSIHD.chd

Is there a command to set the cd-rom to null when just using a SCSI hard-drive?