soohong@gondor.cs.psu.edu (Soohong Kim) (01/31/89)
Hi. I need some pointers/advice on 8"DSDD floppy controllers and
5" High Density drives compatible with TEAC's FD55GFR (can rotate in
**360 rpm** and handle 8" formats!).
I have some 5" floppy diskettes written in an unusual (at lease in
U.S.) format which Japanese people call 2HD (Double side/High density)
and is the same format as 8" DSDD disks use. (Different from IBMPC's
High density format). i.e., 1.2MB capacity, 77 tracks, 1024 bytes/sector,
360 rpm. (BTW, can anyone let me know what is IBMPC's High density
format? What format do 3.5" High Density drives (1.44MB type) use?)
The goal is:
1. to be able to read the contents of these diskettes
2. to be able to write on them.
Reading is the primary concern at this moment, and I am looking for a
way of achieving this goal. One way is to buy an appropriate drive (and
a controller for IBMPC, if necessary) and let it talk to IBMPC.
I'd choose this way since "Disk conversion service" is very expensive
when the amount of data involved is huge, and because it would be great
to be able to keep my data in that format (In fact, my machine is not an
IBM compatible - it's NEC PC-9801F which has two 720K drives - and more
recent versions of PC-9801 have 2HD drives.)
So I'd appreciate any kind of info on:
1. 8"DSDD Controllers for IBMPC (XT, AT or PS2/30)
2. 5" Drives that can rotate 360 rpm like FD55G(360 rpm, fixed) and
FD55FGR(300rpm/360rpm switchable) - Some of them I know are:
Mitsubishi M4854, Matsushita JA-581, Hitachi HFD516B,
TEAC FD-55G, TEAC FD-55GFR, YE-data YD-380T, NEC FD1157C,
and NEC FD1157D.
Any other drives of this kind missing?
Where can I buy any one of those in the US?
Is there such a drive with VFO sitting in the drive?
3. Any other more attractive alternatives?
(I am hardware type and good in assembly languages and I/O drivers)
4. What is IBMPC's High density formats (3.5", 5")? - Just curious
5. What is FD-55GFV ?
For Your Info: 5"FDD specs
DSDD 2DD 2HD
--------------------------+--------+--------+--------
Capacity (Bytes) | 360K | 720K | 1.2M
Transfer rate (Kbits/sec) | 250 | 250 | 500
Rec. density (bits/inch) | 5876 | 5922 | 9646
Track density(tracks/inch)| 48 | 96 | 96
Encoding | MFM | MFM | MFM
# cylinders | 40 | 80 | 77
rotation speed (rpm) | 300 | 300 | 360
--------------------------+--------+--------+--------
---Soohong Kim
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