> EIDE-based flash drives have become very inexpensive. Some
> embedded systems use CompactFlash boards.
Can you set flash drives to be write-only? Sorry if this is a basic
question, but the only EIDE mass-storage devices I've used are more
Write only? Sure, that's been around since at least 1972!
If you mean READ only, some of Sandisk's products (not their normal consumer
grade Compact Flash disks) have a read only mode. Some of which even have a
mode where you can blow a fuse inside the chip with a special instruction,
and make it read-only forever.
Someone else made a solid state flash based IDE compatible drive, too, that
had an option for "write once" per sector (yet could be all blanked using
another special command). I know they wrote a module for OS9 to support it
using its native filesystem (most FS's don't like being unable to write to
whatever they want, whenever they want). It may have been Atmel.