---

Hardwaretest: HD-Floppy 'Power M-Disk Amiga A4000' (von Patrick James)

»PRODUCT NAME

Power M-Disk Amiga A4000


BRIEF DESCRIPTION

A half-speed 1.76 MB (high density) floppy drive for the A4000.
The drive is a slim line device (1"), with a face plate, so can be used in
both any Big Box Amiga or an Amiga 1200 Tower. An external version and a
drive mechanism to be fitted into a desktop A1200 are also available.


AUTHOR/COMPANY INFORMATION

Name: MicroniK Computer Service
Address: Brückenstraße 2
D-51379 Leverkusen-Opladen
Germany

Telephone: +49 - (0) - 2171 - 7245 - 24
FAX: +49 - (0) - 2171 - 7245 - 90

E-mail: order or service@micronik.de
World Wide Web: http://www.micronik.de/


LIST PRICE

£54.95 (Pounds Sterling)

All versions of the drive have the same price.


DEMO VERSION

None


SPECIAL HARDWARE AND SOFTWARE REQUIREMENTS

Any Amiga, with a 3.5" drive bay
AmigaDOS 2.x or better is required for the use of high density
floppy disks


COPY PROTECTION

None


MACHINE USED FOR TESTING

Amiga 2000, revision 6.2
Full ECS chipset
1 MB Chip RAM, 48 MB Fast RAM
Ext. Power Computing XL Drive

Phase5 Blizzard 2040/40 MHz
VillageTronic Picasso IV 1.2, 4 MB
GVP 4008 SCSI
GVP IO Extender
VillageTronic Ariadne Ethernet

1.2 Gigabyte Quantum Fireball
Iomega Zip 100
Sony CDU-55S CDROM

AmigaDOS 3.1 (Kickstart 40.63, Workbench 40.42)
SetPatch 40.16


INSTALLATION

The first part of the installation involves the removal of the
floppy drive being replaced. This is heavily dependent on the Amiga model
or tower case in use, so it would be impossible to describe fully. Once
the drive has been physically mounted in a 3.5" bay, the power and data
cables need to be correctly actached to the drive. In most cases, the
cable connectors will have been manufactured so that they can only be
connected one way. With that done, the drive should be usable immediately
and no patch has to be installed.

If the drive is being installed as DF1:, a jumper on the drive
has to be correctly set, to distinguish between DS0 and DS1. A label
on the drive explains this. Alternatively this may be determined by a
twist in the floppy data cable. In an Amiga 2000, J301 has to be
closed, before DF1: will be recognised. Although the drive was
intended for use in the A4000, there is nothing to stop the drive
being used in any other Big Box Amiga or tower. Full instructions for
fitting drives in Amiga 2000, 3000 and 4000s can be found at:

http://www.nationalamiga.com/technical/ ... rives.html

If you want to access MSDOS disks you will have to mount PC0:,
assuming the drive is DF0:. This involves double clicking on the
DOSDriver for PC0: (Storage/DOSDrivers). A more practical solution is
move the PC0 icon to Devs:DOSDrivers, allowing access everytime the
Amiga is rebooted.


REVIEW

Although floppy drives have become less useful due to the
popularity of removal media for backing up and CDROMs for software
distribution, they are still required. The need for high density
disks on the Amiga is not instantly obvious as only the A4000 has ever
come with one fitted as standard, so no Amiga software has ever been
distributed on high density disks. Backing up a hard disk to high
density floppies is not much more practical than using double density
floppies.

The need for high density drives comes primarily from
emulation, something which the Amiga is very good at. Macs and PCs
have had, as standard, high density drives for sometime, so use of
their software and the transfer of larger files, in the absence of a
network, requires a high density drive. This is especially true when
installing an operating system for use with an emulator.

Normally, Amigas cannot support high density drives because PC
drives run at the normal spindle speed of 300 rpm. Movement of data
in high-density mode requires a 500 kilobaud data pump in the floppy
path. The Amiga chips can only handle around 400 kilobauds. The
Amiga runs its floppy data rate at the older double density standard
of 250 kilobauds. The drives in the A4000 work round this by running
at 150 rpm, consequently giving slower performance with high density
disks. The MicroniK drive employs the same technique, which is fine
for minimal usage for in double density mode, as the drive runs at
approximately normal Amiga speed.

If you want faster access, there have been other attempts to
work round the problem with mixed success. The Power XL Drive uses a
buffer to handle the data sent to the Amiga. This, as the DiskSpeed
results below show, works reasonably well. The other solution is the
untested Catweasel board, which basically acts as a replacement floppy
controller.

Here are some results given by DiskSpeed
(disk/moni/DiskSpeed42.lha). DF3: is a regular 880 KB floppy drive
for comparison, DF2: the XL drive and DF0: the MicroniK drive. All
drives had 20 buffers.

DF3: 880 KB FFS ; The control

Testing directory manipulation speed.
File Create: 1 files/sec
File Open: 10 files/sec
Directory Scan: 41 files/sec
File Delete: 43 files/sec

Seek/Read: 3 seeks/sec

Testing with a 32768 byte, MEMF_FAST, LONG-aligned buffer.
Create file: 11647 bytes/sec
Write to file: 6812 bytes/sec
Read from file: 22755 bytes/sec

Testing with a 32768 byte, MEMF_FAST, WORD-aligned buffer.
Create file: 11565 bytes/sec
Write to file: 6812 bytes/sec
Read from file: 22755 bytes/sec

Testing with a 32768 byte, MEMF_FAST, BYTE-aligned buffer.
Create file: 8359 bytes/sec
Write to file: 953 bytes/sec
Read from file: 18703 bytes/sec

--

DF2: Power XL Drive 1760 KB FFS

Testing directory manipulation speed.
File Create: 1 files/sec
File Open: 8 files/sec
Directory Scan: 40 files/sec
File Delete: 40 files/sec

Seek/Read: 2 seeks/sec

Testing with a 32768 byte, MEMF_FAST, LONG-aligned buffer.
Create file: 11565 bytes/sec
Write to file: 3051 bytes/sec
Read from file: 23461 bytes/sec

Testing with a 32768 byte, MEMF_FAST, WORD-aligned buffer.
Create file: 11538 bytes/sec
Write to file: 3062 bytes/sec
Read from file: 23294 bytes/sec

Testing with a 32768 byte, MEMF_FAST, BYTE-aligned buffer.
Create file: 7783 bytes/sec
Write to file: 744 bytes/sec
Read from file: 18204 bytes/sec

--

DF0: MicroniK Power M-disk 1760 KB FFS

Testing directory manipulation speed.
File Create: < 1 files/sec
File Open: 5 files/sec
Directory Scan: 41 files/sec
File Delete: 41 files/sec

Seek/Read: 1 seeks/sec

Testing with a 32768 byte, MEMF_FAST, LONG-aligned buffer.
Create file: 6898 bytes/sec
Write to file: 2000 bytes/sec
Read from file: 22190 bytes/sec

Testing with a 32768 byte, MEMF_FAST, WORD-aligned buffer.
Create file: 6898 bytes/sec
Write to file: 2000 bytes/sec
Read from file: 22341 bytes/sec

Testing with a 32768 byte, MEMF_FAST, BYTE-aligned buffer.
Create file: 5234 bytes/sec
Write to file: 510 bytes/sec
Read from file: 15312 bytes/sec

These results, as known, show the XL drive to perform slightly
under the normal drive and the MicroniK drive to performe slower still.


DOCUMENTATION

There was no documentation, other than a sticker on the drive,
which explains the jumper settings of the drive itself (DF0: or DF1:). If
you are not confident fitting an internal drive, without instructions, go
for the external version.

No manual is really necessary as the floppy and power cables will
only fit in one way and no software patch is required. The question of
instructions was asked to Blittersoft giving the following response:

"> 2. Is any documentation meant to be included with the Micronik
> HD floppy drive for the A4000?

No, it simply plugs in. Jumpers set DF0 or DF1 (internal)."


LIKES

The drive does not require a patch to be used, unlike the
Power XL Drive. The drive was to easy to install and provides access
to Amiga, MSDOS and Macintosh high density disks, through CrossDOS and
CrossMAC or ShapeShifter.


DISLIKES AND SUGGESTIONS

A manual, including details of the Amiga motherboards' own jumper
settings concerning floppy drives, is definitely required. The mechanism
costs considerably more than a standard full speed high density floppy
drive available for PCs.


COMPARISON TO OTHER SIMILAR PRODUCTS

The drive performs exactly the same as the half speed drive
found in all A4000s (except Amiga Technologies' Towers) and some
A3000s. Power Computing's XL uses a buffer and patch to attempt to
run nearer full speed. This makes installation more complicated.
That drive also costs more. The reviewer and others have encountered
problems with that drive and Shapeshifter, which does not like the
drive's buffer. Meanwhile, others have reported no such problems with
that drive.

Another option which gives access to cheaper, full speed high
density floppy drives, among other interfaces is the Catweasel board
for the A1200/A4000. The cost of a Catweasel and a full speed drive
is not much more than the MicroniK mechanism. The board is also
available as a Zorro II card, called Buddha, featuring several IDE
interfaces. The Catweasel cannot be used to add a floppy drive to an
Amiga 500.


BUGS
None found or suspected


VENDOR SUPPORT

The reviewer is not associated with MicroniK or Blittersoft, a
UK distributer in any way.

An e-mail sent to Blittersoft, for the purpose of obtaining
information for this review, was answered very promptly. Both have
support by e-mail and their WWW sites.


WARRANTY

Unknown, presumably 12 months like other products sold, in the
UK, by Blittersoft.


CONCLUSIONS

This drive does exactly that which it is intended to. It is
noticeably slower when using high density disks. This however is a
limitation of the Amiga's hardware.

This product receives 4.5 stars out of a possible 5 because of
the absence of installation instructions.

All Amigas should have a high density drive. Hopefully, new
Amigas will have the facility for using cheap, full speed high density
drives.


COPYRIGHT NOTICE

Copyright 1998 Patrick James, referred to as "the reviewer",
but may be freely distributed, beyond the normal distribution of
c.s.a.reviews.«