Spirit HDA-506 interface for the Amiga 500/1000

Utilities provided include the low-level formatter, mapbad program, Park program and scripts to initialise your hard disk for first boot.  They work, but are a not quite optimised.

HDA506 Formatter

‘Park’ is worth mentioning, as some of the audience won’t be aware of its function. These drives are quite literally dumb, and need to be told what to do.  When powering off, they’ll just spin down leaving the heads where they were meaning a jolt would cause the head to crash into the disk platter, causing potential damage.  Parking moves the heads to the outermost cylinder, which is unused for data meaning a head crash should not cause problems.  Parking drives before powering down is therefore a good habit.  As a side note, the ST-251 drive did autopark as, when power is removed, the drive motor acts as a generator causing the stepper motor to move the heads to a safe position which strikes me as a beautifully elegant piece of engineering.

HDA506 driver contents

Kickstart 1.3 or higher is required to support autobooting.  The device does not support the RDB standard, so the autoboot process is a bit of a kludge: the EPROM code assumes that the first 6 cylinders of the disk are the autoboot partition using OFS, and mounts them as such.  This small partition then contains just enough to mount the rest of your disk (or disks) from hand-crafted mountlist entries. Naturally more filesystems such as FastFileSystem or whatever your personal penchant is can be installed and used, too.

Given the device was designed to work with Kickstart 1.2 originally and the autoboot capability had to be designed with incomplete specifications, this is forgivable.