HDDRIVE yes or no!
23-Jun-93 01:01:18
Sb: #104418-HDDRIVE yes or no!
Fm: Ronald B. Romine 70322,1525
To: Christian Busse 100121,1360
About those HiD floppy drives…. The floppy "controller" in the
Amiga can handle a max of 300Kps of data at a time. This was ok
since most DSDD 3.5 drives were 250Kps at a speed of 300rpm. The
standard (IBM) HiD floppy (1.44K) does a transfer of 500K at 300rpm,
which the Amiga can not handle.
Commodore contacted Chinon and commissioned a special dual-speed
floppy for the Amiga (the FB-357A & FZ-357A models). These drives
run at 300rpm at DD for 250Kps transfers, and 150rpm at HiD for
250Kps transfers.
A new trackdisk.device was developped for 2.0 that could handle the
HiD mode of the HiD/DD floppy drives. When a diskette was inserted
into the drive the system could auto-detect if it was a HiD or DD
density, and format it accordingly.
However, there was a bug that prevented mixing of HiD & DD drives
with the 2.04 trackdisk.device. Utilities like HD-Fixer, could patch
around the bug.