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#!/usr/bin/perl
#
# This creates four empty UFD-DOS volumes of ~15 MB each,
# specifically 238x256x256 = 15,597,568 (0xee0000) bytes,
# which is the largest volume that UFD-DOS can safely address.
#
# The total capacity is 62,390,272 bytes, which should fit on
# a "64 MB" CF card even with the "modern" definitions of 64 MB...
#
use bytes;
binmode STDOUT;
$at = "\xc0" x 256; # Fill for uninitialized sectors
$ff = "\xff" x 256;
for ( $v = 0 ; $v < 4 ; $v++ ) {
# Track 0: Sector 14 -> bitmap, 15 -> init bitmap, 16+ -> dirmap?
for ( $i = 0 ; $i < 14 ; $i++ ) {
print $at;
}
for ( $i = 14 ; $i < 16 ; $i++ ) {
# First cluster (32 sectors) occupied by system info
# There seems to be a bug in UFD-DOS that it will continue
# an extent out from the end of the disk if there is not
# a "busy" cluster at the end of the bitmap. Thus we limit
# ourselves to 238 tracks.
# 239 bytes occupied by cluster information (0 for empty; the first
# should be 80 to protect the system sectors)
# (the last must be FF
# for the reason described above)
# 16 bytes occupied by root directory information (01 for empty)
# 1 spare byte (always zero?)
# THIS IS THE REAL ONE...
print "\x80", "\x00" x 237, "\xff", "\1" x 16, "\0";
# HACK TO TEST UNDER NEAR FULL CONDITIONS
# print "\xff" x 237, "\x00", "\xff", "\1" x 16, "\0";
}
for ( $i = 16 ; $i < 32 ; $i++ ) {
# Root directory sector
print "\0" x 16, "\xff" x 240;
}
for ( $i = 32 ; $i < 256 ; $i++ ) {
print $at;
}
# Track 1-237
for ( $i = 1 ; $i < 238 ; $i++ ) {
# Sector
for ( $j = 0 ; $j < 256 ; $j++ ) {
print $at;
}
}
}
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