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dmk2cw
Name dmk2cw - Write a DMK floppy disk image file onto a disk using a Catweasel controller Syntax dmk2cw [options] filename.dmk Description The dmk2cw program uses the Catweasel universal floppy disk controller to write a floppy disk image to an actual disk. The image file is expected to be in the DMK format first used by some TRS-80 Model I/III/4/4P emulators. If you have a JV1 or JV3 image to write to disk, run jv2dmk on it first. The DMK image is exactly reproduced on disk, as far as possible, including the positioning and spacing of sectors and the content of gaps. Thus even so-called copy protected disks can be written cor- rectly and should work on the hardware they were made for. Currently, dmk2cw can write all formats that can be written by the Western Digital 177x/179x disk controllers used in the original TRS-80 machine, all formats that can be written by the NEC 765-compatible floppy disk con- trollers used in PCs, and the Digital Equipment Corporation RX02 for- mat. Even formats that mix FM (single density) and MFM (double/high density) on the same track can be written. The dmk2cw program usually guesses the drive type and disk format to be written by measuring the rotational speed of the drive (300 or 360 RPM) and checking the track length and other fields in the DMK file, but you can override this with command line arguments if needed. The program does not automatically double-step if you are writing a 40-track disk in an 80-track drive, however; see the -m flag for this. Also, if you are using a single sided drive, see the -s flag. Versions of dmk2cw exist for both Linux and MS-DOS. On Linux, dmk2cw must be run as root. If the program is made setuid to root, it drops its root privileges as soon as it has obtained access to the block of I/O ports it needs to directly access the Catweasel. On Windows 95, dmk2cw.exe can be run in an MS-DOS Prompt box. On plain MS-DOS, cw2dmk.exe needs the program cwsdpmi.exe (included) to provide DPMI functionality; make sure it is in the same directory as cw2dmk.exe or in another directory on your path. dmk2cw accesses the hardware directly, so it must not be used at the same time as any other Catweasel software. In particular, on Linux, do not load Michael Krause's "cwfloppy" driver at the same time, and on MS-DOS, do not load the "catbase" driver that comes with the Catweasel. For more information about the Catweasel controller and other software that works with it, see: http://www.jschoenfeld.com/ http://www.soundtracker.org/raw/ For information about the DMK file format and the emulators that use it, see: http://discover-net.net/~dmkeil/ http://www.tim-mann.org/xtrs.html Options -d drive Specify the drive unit number, 0 or 1. Default: 0. -v verbosity Specify how much output is printed. Larger numbers select more output. The default setting is 1. 0 No output. 1 Print progress information. 2 Also dump the bytes being written, prefixing each with the encoding used. This option is primarily for debug- ging purposes. The prefixes used are as follows: "-" means the byte is skipped (it was padding in the DMK file), "F" encoded as FM data, "I" encoded as an FM index address mark, "A" encoded as an FM data address mark or ID address mark, "M" encoded as MFM data, "J" encoded as an MFM pre-index address mark, "B" as an MFM pre-data or pre-ID address mark, and "X" as RX02-modified MFM data. 3 Like 2, but also dump the Catweasel samples generated for each byte. This option is primarily for debugging pur- poses. -p port For the Catweasel MK1 (ISA), port should be the I/O port base, or 0 to default to the factory setting of 0x320. For the Catweasel MK3 or MK4 (PCI), port should be 0 for the first Catweasel card in the machine, 1 for the second, etc. The default is 0. -k kind Specify the type of drive and type of media in use. This option is usually not needed, as dmk2cw will typically guess correctly. 1 5.25-inch SD/DD disk in 1.2MB drive 2 5.25-inch SD/DD disk in 360KB/720KB drive, or 3.5-inch SD/DD disk 3 5.25-inch HD disk, or 8-inch SD/DD disk 4 3.5-inch HD disk -m steps Step multiplier, 1 or 2. A step multiplier of 2 is used when writing a 40-track (or 35-track) disk in an 80-track drive. Default: 1. If you set -m2, you should bulk-erase the media first to eliminate residual magnetization from the odd numbered tracks that may cause problems when the disk is read in a 40-track drive. -s sides Maximum number of sides, 1 or 2. Use -s1 if your physical floppy drive has only one head (that is, if it can only write to side 0 of the disk). If you forget to do this and the DMK file has space reserved for side 1 data (even if there are no valid sectors in that space), dmk2cw will overwrite the side 0 data on each track of the media with the side 1 data. The remaining options usually do not need to be changed from their default values. -c clock Catweasel sample rate multiplier. 1 selects 7.080 MHz (about 140 ns), 2 selects 14.161 MHz (about 70 ns), and (on Catweasel MK3 and MK4 only) 4 selects 28.322 MHz (about 35 ns). Default: 2. -o plo[,phi] Specifies the number of nanoseconds to advance or retard transi- tions for write precompensation. The actual distance between transitions is always rounded to a multiple of the Catweasel clock period (-c option), so it is pointless to make adjustments much finer than that value. If one value is given, the same precompensation is used on all tracks. If a pair of values plo,phi is given, plo is used on track 0 and phi on the highest track, with tracks between interpolated linearly. Default: 140ns. Exactly what does this option do? The magnetic flux transitions on a floppy disk tend to move slightly farther apart if they are recorded very close together, thus lengthening the short inter- vals and shortening the long ones, a phenomenon sometimes called bit-shifting. When a disk is recorded, the disk controller ordinarily applies write precompensation to reduce this effect; that is, it makes the short intervals extra short and the long ones correspondingly longer, especially on the inner, higher- numbered tracks. In dw2dmk, if the shortest legal interval appears immediately to the left (or right) of a longer one, the flux transition between them is moved to the left (or respec- tively, right). In general, disks need more precompensation on the inner (higher-numbered) tracks than on the outer tracks, and this effect is more pronounced for larger disks where the difference in length between the inner and outer tracks is greater. The default value of 140ns for all tracks seems to work reasonably well on 3.5-inch and 5.25-inch disks, though it is surely not optimal. For 8-inch disks, a few experiments with the testhist program suggest that -o70,700 is a good value -- it makes tracks 1 and 76 have much more similar histograms than if a constant value is used. If you have trouble reading disks written by dmk2cw with a regular floppy disk controller, try using testhist to compare track histograms of natively-written media that read successfully in your controller with media written by dmk2cw. If there is a substantial difference, try different -o values to see if you can get dmk2cw to write disks that are more similar to the native disks. -h hd For -h0 or -h1, set the HD line on the floppy bus to the indi- cated value. For -h2, set the HD line on the floppy bus to 0 for tracks 0 to 43, to 1 for tracks greater than 43. For -h3, set the HD line on the floppy bus to 1 for tracks 0 to 43, to 0 for tracks greater than 43. For -h4 (the default), the line is set according to the disk kind (-k flag); to 0 for -k1 and -k2; to 1 for -k3 and -k4. -l len Causes dmk2cw to ignore any data beyond the first len bytes in the DMK image of each track. This option is applied before -g or -i. It has no effect if len is greater than the track data length recorded in the DMK image. -g igno Causes dmk2cw to ignore the first igno bytes in the DMK image of each track. If igno is negative, an extra -igno bytes of pad- ding are inserted at the beginning of each track. -i ipos If this option is given, dmk2cw forces the first IAM (index address mark) encountered on each track to be exactly ipos bytes from the physical start of the track, by ignoring bytes or adding padding at the start of the track as with the -g flag. The default is -1, which disables this feature, instead record- ing the gap exactly as in the image. Note that if you set ipos too small, there will not be enough bytes in the initial gap for the IAM to be recognized when the disk is read. -r reverse If reverse is 1, dmk2cw reverses the sides of the disk; that is, it writes side 0 of the DMK file to physical side 1 of the disk and side 1 of the DMK (if any) to physical side 0 of the disk. The default is 0, which does not reverse the sides. This option is most likely to be useful if you want to write a separate 1-sided DMK image to each side of a disk in a double-side drive. You can do this by running dmk2cw twice, first writing the head 0 image using -s1 -r0, then the head 1 image using -s1 -r1. -f fill If the track data being written (after possibly being shortened by the above options) is not sufficient to fill the physical track, dmk2cw writes the rest of the physical track with a fill pattern. By default (with fill = 0), if the last data byte of the track was encoded in FM or RX02, the fill pattern is 0xff encoded in FM; if the last data byte was encoded in MFM, the fill pattern is 0x4e encoded in MFM. With fill = 1, dmk2cw erases the remainder of the track and writes nothing (not avail- able on Catweasel MK1 or MK3). With fill = 2, the fill pattern is a sequence of very long transitions, which also effectively erases the remainder of the track. With fill = 3, there is no fill; the Catweasel stops writing at the end of track, leaving whatever was previously on the disk intact. With fill = 0x1nn, the fill pattern is 0xnn encoded in FM. With fill = 0x2nn, the fill pattern is 0xnn encoded in MFM. -y testmode Set various undocumented test modes for debugging. Diagnostics dmk2cw: Error reading from DMK file The DMK file was opened successfully, but a read from it failed. dmk2cw: File is not in DMK format The specified disk image file was opened successfully, but it was not in DMK format. If you have disk images in JV1 or JV3 format, use jv2dmk to convert them to DMK format before using them with dmk2cw. dmk2cw: No access to I/O ports On Linux, dmk2cw must be made setuid to root or be run as root, or it will not be able to access the Catweasel's I/O ports and this error message will appear. dmk2cw: Failed to detect Catweasel A Catweasel card was not detected at the specified I/O ports. dmk2cw: Drive 0 was not detected, but drive 1 was dmk2cw: Drive 1 was not detected, but drive 0 was dmk2cw: Failed to detect any drives The specified drive (see -d option) was not detected, or no drives were detected. Cabling and drive selection can be con- fusing, so try the other drive number before giving up, espe- cially if you saw some drive activity before this message was printed. Note: In versions prior to 3.0, dmk2cw used the oppo- site drive numbering convention from the bundled Catweasel soft- ware supplied by Individual Computers. This has now been cor- rected. dmk2cw: Disk is write-protected This message usually means what it says. A 3.5-inch disk should have its write-enable slider closed. A 5.25-inch disk should not have a write-protect tab covering its notch. An 8-inch disk should have a write-enable tab covering the appropriate notch. It might also appear in some cases if the drive is not connected properly, the door is not closed, the disk is inserted upside- down, etc. dmk2cw: Failed to guess drive kind; use -k This message is printed if drive/media autodetection fails. Either the drive speed could not be measured, or the track length was not one of the common values used in most DMK files. You can specify the kind of drive and media in use with the -k flag. dmk2cw: No disk in drive This message usually means what it says, that there is no disk in the drive. It might also appear in some cases if the drive is not connected properly, the door is not closed, the disk is inserted upside-down, etc. dmk2cw: Write error Either the drive reported that it was not ready when the Catweasel tried to write to it, or no index hole was detected. This message usually means that there is no disk in the drive. It might also appear in some cases if the drive is not connected properly, the door is not closed, the disk is inserted upside- down, etc. dmk2cw: Drive is 1-sided but DMK file is 2-sided This message means that there is space reserved in the DMK file for two sides, and some apparently valid data was found on side 1, but you gave the -s1 flag to say that your disk drive is only one-sided. Authors dmk2cw was written by Timothy Mann, http://tim-mann.org/. It uses low- level Catweasel access routines written by Michael Krause. dmk2cw is free software, released under the GNU General Public License. Thanks to Jens Schoenfeld for providing documentation on programming the Catweasel hardware. Thanks to David Keil for designing and documenting the DMK file format for floppy disk images. The DPMI host cwsdpmi.exe is free software, written and copyrighted by Charles W. Sandmann and released under the GNU General Public license. You can download the source code and/or binary updates for this program from ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2misc/. Look for files with names of the form csdpmi*.zip. Note: the highest version that has been tested with dmk2cw at this writing is 5.