Copyright (c) 1980 by Laboratory Microsystems
4147 Beethoven Street
Los Angeles, California 90066
1.0 General description
The Z-80 Floppy Disk Test is a general purpose utility for testing or
initializing a diskette. It requires a Z-80 microprocessor, at least
16 kbytes of random access memory, two flexible disk drives, and the
Digital Research CP/M 2.x operating system. Program mode and area of
diskette to be tested are controlled from the keyboard. Errors may be
audited on the console or the line printer.
As supplied on the distribution diskette, the program is configured to
test a soft-sectored, single density disk with 77 tracks, 26 sectors
per track, and 128 byte sectors. If you are using a different type of
disk drive, the number of tracks and/or sectors per track may be
specified during the initialization dialogue.
The program does not exhaustively check out the disk drive, and any
errors detected by the program must be interpreted with care.
Intermittent errors occurring throughout a broad range of disk
addresses probably indicate a problem with the disk drive unit.
Errors indicated at consistent addresses within adjacent tracks may
result from a worn or damaged flexible disk. Error free execution of
the test certainly indicates an intact and usable diskette, and also
is fairly good evidence of proper operation of your disk drive. Note
that the program is rather insensitive to drive problems related to
head movement, since the diskette is addressed in a smooth sequential
manner.
2.0 Installation
Mount your system disk in drive A, and the distribution disk in drive
B. Use the PIP utility to transfer the test program onto the system
disk:
A>pip a:=b:dtst.com [v]
Now remove the distribution disk from drive B and store it as the
backup copy.
3.0 Using the Test Program
Put your system disk in drive A, boot up the CP/M operating system, and
type:
A>dtst
The test program will load into memory and print the identifying
message:
Laboratory Microsystems Disk Test version 1.0
If there is inadequate memory in the transient program area, or if the
operating system is not CP/M version 2.0 or greater, the program will
immediately print a warning message and exit. Otherwise, the test
proceeds to the initialization dialogue. The test mode is set via a
series of questions presented on the system console. Answers calling
for an alphabetic character may be upper or lower case; a carriage
return is not required. Answers calling for a number must be two
digits, or one digit followed by a carriage return.
Itemize errors? Y or N If answered y, each error
detected is audited on the
selected device. If answered
N, only the total error count
is printed at the end of each
pass.
Console or Printer? C or P If itemizing errors, select
the device on which the
itemized error listing will be
printed.
Lock on read or write? N, R, or W N = no locks. R = lock on
read mode (no data is written
to the disk --- useful for
detecting any damaged areas on
the media). W = lock on write
(all data on the disk is
destroyed --- this may be used
to erase a diskette by also
locking on pattern)
Restore original data? Y or N Y = restore existing data on
diskette after testing each
sector. N = do not restore
existing data. Test runs much
faster when restore mode is
not used.
Lock on data pattern? Y or N Y = user wishes to specify
specific data to be used as
the test pattern. N = random
data pattern is generated by
the test program.
Enter data pattern hex 00-FF If you answered Y to Lock On
Pattern, enter the eight bit
data pattern to be used during
disk testing. If you answered
N, this question is bypassed.
Drive to be tested B, C, or D Specify disk drive to be used
for diskette testing. In
order to prevent accidental
destruction of the system
disk, the use of drive A is
not allowed.
Test all tracks? Y or N Y = test all tracks (00-76) in
sequence. N = user wishes to
specify range of tracks (may
be used to test only part of a
diskette, or if disk drive is
other than standard 8 inch
single density).
First track to test decimal 00-76 If you answered N to Test All
Tracks, specify here the
number of the first track to
test.
Last track to test decimal 00-76 If you answered N to Test All
Tracks, specify here the
number of the last track to
test. Must be the same or
greater than the number of the
first track to test.
Test all sectors? Y or N Y = test all sectors (1-26) in
sequence. N = user wishes to
specify range of sectors (may
be used to test only part of
each track, or if disk drive
is other than standard 8 inch
single density).
First sector to test decimal 01-26 If you answered N to Test All
Sectors, specify here the
number of the first sector to
test on each track.
Last sector to test decimal 01-26 If you answered N to Test All
Sectors, specify here the
number of the last sector to
test on each track. Must be
the same or greater than the
number of the first sector to
test.
How many test passes? decimal 01-99 Enter the number of test
passes to be made on the
diskette. At least one pass
is always made even if you
enter zero.
After entry of the number of test passes, the program immediately
begins executing. The program may be interrupted by pushing any key,
however response may be delayed for several seconds depending on the
speed of the processor and disk drive. Do not stop the test by
resetting the computer system if you are using restore mode, or
unpredictable amounts of data may be lost.
4.0 Error Listing
Errors detected by the program may be itemized on the system console
or the line printer. The pass, drive name, track, and sector where
the error occurred are listed. All numbers are in decimal. The error
type is designated at the right. In the explanations below, "hardware
error" signifies an error status code returned from the low level disk
driver, and usually means a CRC fault or seek incomplete.
error type explanation
---------- -----------
read error - original data If running in restore mode, hardware
read error noted as the original data
was being loaded into memory.
write error - test data Hardware error noted as the test data
pattern was being written on the
diskette.
read error - test data Hardware error noted as the test data
pattern was being read back from the
diskette.
compare error - test data Difference was found between the data
pattern that was written to the
diskette and the data that was read
back.
write error - restore phase Hardware error noted as the original
data was being written back to the
diskette.
read error - restore phase Hardware error noted as the restored
original data was being read back for
verification.
data cannot be restored Compare error found between the
original data rewritten to the
diskette and the same sectors read
back for verification.
5.0 Program areas of interest to users
To use the program on other types of disk drives, it may become
necessary to change the first two locations given below. This may be
done be reading in the COM file with DDT, patching the desired
location, and SAVEing a new COM file.
0119H (8 bits) Sector skew flag. If byte=0, skew is not used. If
byte=1, remap sector numbers as given in the sector
translation table. On Z-80 systems at 4 mhz, skew is not
needed and this byte may be left zero. On systems with slower
processors, test speed may be improved by use of skew.
0121H (8 bits) Contains the number of digits to be accepted by the
numeric input routines during the initialization dialogue, the
value is two in the distributed version. If test is to run on
a drive with greater than 99 tracks, change the value of this
byte to three.
0122H (16 bits) Contains the address of the sector translation
table. In the distributed program, the table is built with a
skew factor of three, and is 26 bytes long.
