floppymeter - measure raw capacity and exact rotation speed of floppy
This manpage has been automatically generated from fdutils’s texinfo
documentation. However, this process is only approximative, and some
items, such as crossreferences, footnotes and indices are lost in this
translation process. Indeed, these items have no appropriate
representation in the manpage format. Moreover, only the items
specific to each command have been translated, and the general
information about fdutils has been dropped in the manpage version.
Thus I strongly advise you to use the original texinfo doc.
* To generate a printable copy from the texinfo doc, run the
./configure; make dvi; dvips fdutils.dvi
* To generate a html copy, run:
./configure; make html
A premade html can be found at:
* To generate an info copy (browsable using emacs’ info mode),
./configure; make info
The texinfo doc looks most pretty when printed or as html. Indeed, in
the info version certain examples are difficult to read due to the
quoting conventions used in info.
floppymeter [-f] [-w warmup-delay] [-W window]
[-c cycles] [-h] drive
The floppymeter program measures characteristic parameters of a floppy
drive and floppy controller, such as the rotation speed of the drive,
the data transfer rate of the controller, and the resulting raw
capacity of a disk track. To use this program, insert a disposable
floppy in the drive, and type floppymeter --density, where density
describes the density of the disk used for the test. (Should be one of
dd, hd or ed). CAUTION: the data on the disk will be erased. This
program should be used to verify whether the drive and controller are
out of tolerance if you experience problems with some high capacity
formats. It only needs to be run once per drive: although a disk is
needed to perform the measurements, the measured data only depend on
the drive and the controller, and not on the disk.
To measure the raw capacity of the disk track, the floppymeter program
formats the first track of the drive in a special way that allows it to
read the raw data (gaps and headers) of the disk. Thus, all data
previously stored on that disk is lost.
The rotation speed is measured by timing the return time of a readid
command. In order to gain more precision, the command is issued many
times in a row. During this phase, the number of rotations til the
start of the test, the average time per rotation til the start, and a
sliding average of the times of the last 30 rotations is printed, and
The data transfer rate is deduced from the two parameters above.
At the end of the program, all parameters (raw capacity, duration of
one rotation, and data transfer rate) are printed again, as well as
their relative deviation to the standard value. Finally, it suggests a
capacity deviation description line, which can be directly pasted into
the drive definition file (See section Drive descriptions.).
Usually, the data transfer rate should not deviate more than 150 ppm
from the expected value, and the rotation speed of the drive should not
deviate more than 3000 ppm from the expected value. If these
deviations are bigger, you may get problems with certain high capacity
If the raw capacity of the drive is too small, some high capacity
formats may become unformattable on this drive/controller combo.
If on the other hand, the raw capacity of the drive is too big, you may
get problems when writing to a disk formatted by this drive on another
drive with a smaller raw capacity. In order to avoid this, increase
superformats gap parameter (-G).
-h Prints a short help
--dd Tells the program that we use a Double Density disk.
--hd Tells the program that we use a High Density disk.
--ed Tells the program that we use an Extra Density disk.
-f Runs the measurement non interactively. With this option, the
program doesn’t ask for confirmation, and doesn’t display the
continuously updated values during the rotation speed
This value describes how many rotations are used for the
computation of the sliding average. Default is 30.
Describes the number of rotations clocked during the rotations
speed determination test. Default is 1000.
This program is quite new, and may have bugs. Here are a few suggested
tests to check its sanity:
* The deviation of the data transfer rate solely depends on the
controller. It should not be different between two drives
connected to the same controller. However, the drive rotation
speed may be different for different drives.
* All data transfer rates (for double, high and extra density) are
derived from a same master frequency. Thus the deviation of the
data transfer rate should be independant of the density used.
Fdutils’ texinfo doc