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              HOW-TO: Read 5.25" D-NIX floppys on IBM PC with Linux
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                                                                    Pryss 2018-09-23

On a Linux PC with a 1.2Mb 5.25" floppy drive set the floppy controller to double
sided, quad density:

  root@dec:~$ setfdprm /dev/fd1 ds qd

Use the dd command to read the floppy:

  root@dec:~$ dd if=/dev/fd1 of=tar-file_1of2.img bs=512
  1440+0 records in
  1440+0 records out
  737280 bytes (737 kB) copied, 40.3879 seconds, 18.3 kB/s

All installation media are straight tar-files where the floppy has been treated like
a tape; there are no file system:

  root@dec:~$ tar tvf tar-file_1of2.img
  -rw-r--r-- 10/0           4096 1989-10-19 11:22:12 FILTST.COB
  -rw-r--r-- 10/0            822 1989-10-19 11:22:12 Makefile
  -rw-r--r-- 10/0           3328 1989-10-19 11:22:12 NUCTST.COB
  -rw-r--r-- 10/0           4352 1989-10-19 11:22:13 PACETEST.COB
  -rw-r--r-- 10/0           3328 1989-10-19 11:22:13 PRNTST.COB
  -r--r--r-- 10/0           2816 1989-10-19 11:22:13 RUN.MSG
  -rw-r--r-- 10/0           4096 1989-10-19 11:22:14 SORTTST.COB
  -rw-r--r-- 10/0          11008 1989-10-19 11:22:14 VDTTST.COB
  -rw-r--r-- 10/0           2560 1989-10-19 11:22:14 VERIFY.COB
  -rw-r--r-- 10/0            165 1989-10-19 11:22:14 config.comp
  -rw-r--r-- 10/0           2639 1989-10-19 11:22:15 config.curses
  -rw-r--r-- 10/0           2500 1989-10-19 11:22:15 config.termcap
  -rw-r--r-- 10/0           2559 1989-10-19 11:22:15 config.terminf
  -rwxr-xr-x 10/0            680 1989-10-19 11:22:15 doverify
  -rw-r--r-- 10/0           1309 1989-10-19 11:22:15 gold.def
  -rw-r--r-- 10/0              2 1989-10-19 11:22:37 rcv1patches
  -rwxr-xr-x 10/0          19107 1989-10-19 11:22:16 recover1
  -rw-r--r-- 10/0            592 1989-10-19 11:22:16 recover1i.a
  -rw-r--r-- 10/0          13056 1989-10-19 11:22:17 recover2.big
  -rw-r--r-- 10/0           9984 1989-10-19 11:22:17 recover2.sml
  -rwxr-xr-x 10/0           1861 1989-10-19 11:22:17 recovery
  -rw-r--r-- 10/0           1842 1989-10-19 11:22:17 rmc85call.h
  -rwxr-xr-x 10/0            779 1989-10-19 11:22:18 rminstall
  -rwxr-xr-x 10/0          19091 1989-10-19 11:22:38 rmp
  -rw-r--r-- 10/0           9728 1989-10-19 11:22:37 rmpatch.cob
  -rwxr-xr-x 10/0         390523 1989-10-19 11:22:26 runcobol
  -r--r--r-- 10/0         193536 1989-10-19 11:22:35 runcoboli.a