2 Mar
2023
2 Mar
'23
10:45 a.m.
Resending
Part 2
BTW, for the parameters for DRIVER.SYS, you can abbreviate the /t:80 /s:9 to
"/F:2" (and later, "/F:720")
/0 was "360K"
/1 was "1.2M"
/2 was "720K"
anybody remember the numbers for 8"?
/d:2 meant you wanted the logical drive to use the third physical drive, /d:3
meant you wanted the logical drive to use the fourth physical drive, /d:1
meant you wanted the logical drive to use the second physical drive, /d:0
meant you wanted the logical drive to use the firs physical drive, which you
could do if you used a "360K" format on the disk in the "720K" drive
in A:
during booting.
Machines that had "CMOS Setup" that supported 3.5" disk drives would let
you
use a 3.5" drive as A:
And 5.25" "Quad" drives (NON-HD 96tpi, such as Tandon TM100-4, Teac 55F, or
Shugart/matsushits 465) was generally indistinguishable to the PC from a 3.5"
"720K".
TRIVIAL nits on the webpage (URL that you posted):
TRS80 Model II was 8" drives. (model 1 and 3 were 5.25") Although I have
heard of somebody kludging "1.2M" drives on one, I haven't seen it.
The picture identifying locations shows the FDC on the motherboard. It was on
the FDC board, and "power connectors" is pointing at the drive
internal data connectors; the power connectors are not visible in the picture,
because they are underneath.
"Ive heard stories that the 37-pin external adapter can be used to read/write
older 8 disk drives, but I never saw this in person. 8 disk drives were a bit
before my time."
modifications are needed to the FDC board to do so.
Flagstaff Engineering did so, and sold a modified FDC plus 8" drive.
The configuration switches on the motherboard of 5150 and 5160 can be set for
up to four drives, and those should be discussed?
Yes, as mentioned, with extra floppy drives, demented INSTALL programs, such
as MS-DOS 6.00, will insist on trying to install to your third floppy.
SUGGESTION: a cheap vise works adequately for crimping flat IDC cables; I've
even done them with a block of wood and a hammer, and with vise-grips.
NOTE: when I say "720K", "360K", "1.2M", I am using those as
NAMES for those
disks, formats, and drives, not as necessarily the capacity. I am well aware
that those names don't acknowledge that the "720K" drive is capable of other
formats, ranging from 640K to 800K, (or even more with short gaps, mixed
sector sizes, and/or other tricks). But, I have yet to see, other than
listing sample model numbers, names for the drive that are simple, and less
ambiguous.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
2 Mar
2 Mar
11:02 a.m.
New subject: Booting from B: (Was: Getting QRST files onto
anybody remember the numbers for 8"?
This is the official KB from MS on the topic:
Standard Floppy Disk Formats Supported by MS-DOS
============================================================================
===
Article ID: 75131 - View products that this article applies to.
This article was previously published under Q75131
SUMMARY
By using DRIVER.SYS and/or the DRIVPARM command in the CONFIG.SYS file, you
can select a variety of floppy disk formats for use with MS-DOS. The tables
below describe the standard floppy disk formats supported by various
versions of MS-DOS and show the switches used for DRIVER.SYS and FORMAT.EXE.
MORE INFORMATION
The tables below include information on the following:
Number of heads (sides)
Number of cylinders (tracks)
Number of sectors per track
Total number of sectors
Number of free sectors
Number of sectors per cluster
Total number of clusters
Number of sectors per FAT (file allocation table)
Number of FAT copies
Number of root directory sectors
Number of reserved sectors
Number of hidden sectors
Number of bytes per sector
Number of bytes per cluster
Number of root directory entries
The media descriptor byte for each format
What recording density was used to create the floppy disk
Under what MS-DOS version this format was first supported
What parameter to use with DRIVER.SYS for this format
What parameter to use with FORMAT.EXE for this format
Whether or not the changed-diskette line is supported
NOTES
1.The switches shown for DRIVER.SYS can also be used for DRIVPARM. Example:
The line "Device=C:\DOS\DRIVER.SYS /D:1 /F:9 /C" in the CONFIG.SYS file
specifies that floppy disk drive B is a 2.88-megabyte (MB) 3.5-inch floppy
disk drive that supports the changed-diskette line.
Example: The line "DRIVPARM=/D:1 /F:9 /C" in the CONFIG.SYS file specifies
that the floppy disk drive B is a 2.88-MB 3.5-inch floppy disk drive that
supports the Change line.
Example: The command "FORMAT B: /F:720" formats a double-sided
double-density 720K floppy disk in a 1.44-MB or 2.88-MB 3.5-inch floppy disk
drive that is installed in the computer as floppy disk drive B.
2.The following charts refer to "Clusters," whereas MS-DOS 5.0 and later
refer to "Allocation Units." These two terms are equivalent and describe the
same data structure.
3.Multiple formats with the same DRIVER.SYS switch is NOT an error.
4.Multiple formats with the same media descriptor byte does NOT indicate an
error.
5.Valid media descriptor bytes for MS-DOS are listed below:
Byte Capacity Media Size and Type
---------------------------------------------------
F0 2.88 MB 3.5-inch, 2-sided, 36-sector
F0 1.44 MB 3.5-inch, 2-sided, 18-sector
F9 720K 3.5-inch, 2-sided, 9-sector
F9 1.2 MB 5.25-inch, 2-sided, 15-sector
FD 360K 5.25-inch, 2-sided, 9-sector
FF 320K 5.25-inch, 2-sided, 8-sector
FC 180K 5.25-inch, 1-sided, 9-sector
FE 160K 5.25-inch, 1-sided, 8-sector
FE 250K 8-inch, 1-sided, single-density
FD 500K 8-inch, 2-sided, single-density
FE 1.2 MB 8-inch, 2-sided, double-density
F8 ----- Fixed disk
6.Both track and cylinder numbers are zero-based. For example, 360K
5.25-inch floppy disks have 40 tracks numbered 0 through 39. Similarly, head
numbers and side numbers are also zero-based. For example, 360K 5.25-inch
floppy disks have sides 0 and 1 (corresponding to heads 0 and 1). However
sectors are one-based. For example, 360K 5.25-inch floppy disks have sectors
numbered 1 through 9.
Standard Floppy Disk Formats Supported by MS-DOS
3.5 Inch - Formatted Capacity
720K 1.44 MB 2.88 MB
# of Heads (Sides) 2 2 2
# of Cyls (Tracks) 80 80 80
# of Sectors/Track 9 18 36
Total # of Sectors 1440 2880 5760
# of Free Sectors 1426 2847 5726
# Sectors/Cluster 2 1 2
Total # of Clusters 713 2847 2863
# Sectors/FAT 3 9 9
# of FAT Copies 2 2 2
# of Root Dir Sectors 7 14 15
# Reserved Sectors 1 1 1
# of Hidden Sectors 0 0 0
# of Bytes/Sector 512 512 512
# of Bytes/Cluster 1024 512 1024
# Root Dir Entries 112 224 240
Media Descriptor F9 F0 F0
Recorded Density Double High High
MS-DOS Version Began 3.20 3.30 5.00
DRIVER.SYS Switch /F:2 /F:7 /F:9
FORMAT.EXE Switch /F:720 /F:1.44 /F:2.88
Change-Line Support YES YES YES
5.25 Inch - Formatted Capacity
160K 180K 320K 360K 1.2
MB
# of Heads (Sides) 1 1 2 2
2
# of Cyls (Tracks) 40 40 40 40 80
# of Sectors/Track 8 9 8 9 15
Total # of Sectors 320 360 640 720 2400
# of Free Sectors 313 351 630 708 2371
# Sectors/Cluster 1 1 2 2 1
Total # of Clusters 313 351 315 354 2371
# of Sectors/FAT 1 2 1 2 7
# of FAT Copies 2 2 2 2 2
# of Root Dir Sectors 4 4 7 7 14
# Reserved Sectors 1 1 1 1 1
# of Hidden Sectors 0 0 0 0 0
# of Bytes/Sector 512 512 512 512 512
# of Bytes/Cluster 512 512 1024 1024 512
# Root Dir Entries 64 64 112 112 224
Media Descriptor FE FC FF FD F9
Recorded Density Double Double Double Double High
MS-DOS Version Began 1.00 2.00 1.10 2.00 3.00
DRIVER.SYS Switch /F:0 /F:0 /F:0 /F:0 /F:1
FORMAT.EXE Switch /F:160 /F:180 /F:320 /F:360 /F:1.2
Change-Line Support NO NO NO NO YES
8-Inch - Formatted Capacity
250K 500K 1.2 MB
# of Heads (Sides) 1 2 2
# of Cyls (Tracks) 77 77 77
# of Sectors/Track 26 26 8
Total # of Sectors 2002 4004 1232
# of Bytes/Sector 128 128 1024
# of Bytes/Cluster 512 512 1024
# Sectors/Cluster 4 4 1
Total # of Clusters 497 997 1227
# Reserved Sectors 1 4 1
# of Hidden Sectors 3 0 0
# Sectors/FAT 6 6 2
# of FAT Copies 2 2 2
# Root Dir Entries 68 68 192
Media Descriptor FE FD FE
Recorded Density Single Single Double
MS-DOS Version Began 1.00 2.00 2.00
Change-Line Support NO NO NO
Article ID: 75131 - Last Review: May 12, 2003 - Revision: 2.0
APPLIES TO
.Microsoft MS-DOS 1.0 Standard Edition
.Microsoft MS-DOS 2.11 Standard Edition
.Microsoft MS-DOS 3.1
.Microsoft MS-DOS 3.2 Standard Edition
.Microsoft MS-DOS 3.21 Standard Edition
.Microsoft MS-DOS 3.3 Standard Edition
.Microsoft MS-DOS 3.3a
.Microsoft MS-DOS 4.0 Standard Edition
.Microsoft MS-DOS 4.01 Standard Edition
.Microsoft MS-DOS 5.0 Standard Edition
.Microsoft MS-DOS 5.0a
.Microsoft MS-DOS 6.0 Standard Edition
.Microsoft MS-DOS 6.2 Standard Edition
.Microsoft MS-DOS 6.21 Standard Edition
.Microsoft MS-DOS 6.22 Standard Edition
Keywords: KB75131
11:37 a.m.
New subject: Booting from B: (Was: Getting QRST files onto
On 3/2/23 11:02, Ali via cctalk wrote:
Japanese MS-DOS (used on NEC computers, mostly) used 1024 byte sectors
in 8", 5.25" and 3.5" media. In fact, most USB floppy adapters support
the NEC 1.23M format and Windows NT has understood it (given a capable
drive) for many years.
It's Microsoft, so why it's not included in the table is beyond me.
For example, if you were to use a NEC APC (sold in the US) with 8"
drives, you'd find this format.
Sector size: 1024
Cluster size: 1024
Sectors/FAT 2
Media byte FE
Root directory size 192
--Chuck
anybody
remember the numbers for 8"?
This is the official KB from MS on the topic:
Standard Floppy Disk Formats Supported by MS-DOS
11:56 a.m.
New subject: Booting from B: (Was: Getting QRST files onto
It is indeed strange that, MICROS~1 never seems to acknowledge the
existence of the NEC variant. And yet, it made sense to have the same
disk format parameters for three sizes of disk.
Unfortunately, the otherwise excellent table leaves out the lines for
DRIVER.SYS and FORMAT specifiers (if such existed)
There are, of course, MANY other variants of MS-DOS disk formats, but
mostly created by OEMs, not by Microsoft, and particularly with MS-DOS
2.11 and 3.31 . For example, 80 track 5.25" DD formats, such as Tandy
2000, IBM PC/JX, Dec Rainbow, etc., and 3.5" disks, such as HP, Gavilan,
Data General, etc., before DOS 3.20.
http://www.xenosoft.com/fmts.html (includes formats other than MS-DOS,
such as CP/M, P-System, NEC and other with the Microsoft "Stand-Alone
BASIC")
--
Grumpy Ol' Fred cisin(a)xenosoft.com
>> anybody remember the numbers for 8"?
On 3/2/23 11:02, Ali via cctalk wrote:
> This is the official KB from MS on the topic:
> Standard Floppy Disk Formats Supported by MS-DOS
On Thu, 2 Mar 2023, Chuck Guzis via cctalk wrote:
Japanese MS-DOS (used on NEC computers, mostly) used
1024 byte sectors
in 8", 5.25" and 3.5" media. In fact, most USB floppy adapters support
the NEC 1.23M format and Windows NT has understood it (given a capable
drive) for many years.
It's Microsoft, so why it's not included in the table is beyond me.
For example, if you were to use a NEC APC (sold in the US) with 8"
drives, you'd find this format.
Sector size: 1024
Cluster size: 1024
Sectors/FAT 2
Media byte FE
Root directory size 192
--Chuck
928
days inactive
928
days old
3 comments
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participants (3)
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Fred Cisin