A8XD(1)

NAME
a8xd - Atari 8-bit ATASCII-aware hex dump

SYNOPSIS

a8xd [-i] [-l limit] [-m] [-o offset] [-s [-]seek] [-u] [-v] [infile]

DESCRIPTION

a8xd is a hex dump utility, similar to xxd(1), but it understands and prints ATASCII characters rather than ASCII.

The ATASCII codes are converted to UTF-8, in the same way as a8cat(1). Codes with the high bit set are displayed in inverse video, using ANSI/VT-100 escape sequences.

By default, the output is colorized (see COLORS, below). The colors and inverse rendering apply to both the ATASCII and hex bytes.

Without infile, or if infile is -, a8xd reads from standard input.

OPTIONS

-a  ANTIC mode: treat the input as screen bytes (aka "internal codes") rather than ATASCII. Can usefully be combined with -g or -f.

-f  Like -g, but using the top half of the character set. This is what you'd see on the Atari with GRAPHICS 1:POKE 756,226.

-g  Graphics mode. Changes the printed characters and colorization so it looks like GRAPHICS 1 (or 2) on the Atari.

-i  Print XL/XE International Character Set conversions instead of ATASCII.

-l len
    Stop after dumping len bytes. len may be given in decimal or hex (with leading 0x or $).

-m  Monochrome mode. Disables color, but ATASCII characters with the high bit set are still displayed in inverse.

-o offset
    Add offset to displayed file position. offset can be given in decimal or hex (with leading 0x or $). Negative offsets are allowed, but they will be printed as very large positive numbers in the output (this matches xxd's behaviour).

-s [-]seek
    Start at seek bytes. Without -, this is an absolute offset. With -, it's relative to the end of the file. The - option won't work when reading from standard input. seek may be given in decimal or hex (with leading 0x or $).

-u  Use uppercase letters for hex digits; the default is lowercase.

-v  Verbose. Shows various debug messages that are probably only useful if you're hacking on a8xd.

--  End of options; the next argument is the filename. Use this if you're trying to work with files whose names begin with -.

-h, --help
    Show built-in help and exit.

--version
    Show version number and exit.

COLORS

The default color scheme is:

•   Non-control characters are green. This includes alphanumerics, spaces, and punctuation. These are the characters that ATASCII has in common with ASCII.

•   Graphics characters are yellow. This includes $01 to $1a (the alphabet, with the Control key held down), $60 (the diamond), and $7b (the spade).

•   Codes $00 (null, or ATASCII heart) and $9B (EOL) are red. These characters are used as delimiters, so it makes sense for them to stand out.

•   Cursor control characters are purple. These are characters that perform some action when printed to the E: device. These are:

$1b Escape.

$1c through $1f
    Cursor movement (up/down/left/right arrows).

$7d Clear screen.

$7e Backspace.

$7f Tab.

$9c Delete line.

$9d Insert line.

$9e Clear tab stop.

$9f Set tab stop.

$fd Bell.

$fe Delete character.

$ff Insert character.

    In -f and -g modes, the above doesn't apply. Instead, the colors are (close to) the colors that would appear in GRAPHICS 1, with the default palette.

NOTES

a8xd requires the terminal emulator to support UTF-8 and use a font with the necessary glyphs. The author has tested extensively with urxvt(1) (aka rxvt-unicode) and xterm(1), using the Deja Vu Sans Mono, JetBrains Mono, Liberation Mono, and Symbola fonts. Also kitty(1), xfce4-terminal(1), KDE/Plasma 5's konsole(1), gnome-terminal(1) 3.43.90, and st(1) from suckless.org have been lightly tested and seem to work fine. Even the Linux console works, except that you won't be able to find a console font with all the necessary glyphs (I may create one someday).

a8xd only supports terminals that use ANSI-style escape sequences for color and inverse video. This isn't much of a limitation, since all modern X, Wayland, Mac, etc terminal emulators have support for this... but it might annoy you if you're trying to use an Atari ST with a VT52 emulator as a serial terminal. Sorry.

a8xd supports a useful subset of xxd(1) options. The main things missing are:

•   -r (revert).

•   -include (output as C include) and all options related to it.

•   -g (grouping; a8xd always uses a group size of 1 byte).

•   -E (EBCDIC mode).

•   -p (PostScript/continuous dump).

•   -cols (a8xd only supports 16 column dumps).

•   -b (bits mode).

•   support for files larger than 2GB. This won't be a problem for Atari 8-bit-related files!

•   replacing duplicate lines in the output with *.

COPYRIGHT

WTFPL. See http://www.wtfpl.net/txt/copying/ for details.

AUTHOR

B.  Watson <urchlay@slackware.uk>; Urchlay on irc.libera.chat ##atari.

SEE ALSO

a8cat(1), a8eol(1), a8xd(1), atr2xfd(1), atrsize(1), axe(1), bas2aplus(1), blob2c(1), blob2xex(1), cart2xex(1), cxrefbas(1), dasm2atasm(1), diffbas(1), dumpbas(1), f2toxex(1), fenders(1), listbas(1), listamsb(1), protbas(1), renumbas(1), rom2cart(1), unmac65(1), unprotbas(1), vxrefbas(1), whichbas(1), xex1to2(1), xexamine(1), xexcat(1), xexsplit(1), xfd2atr(1), xex(5), atascii(7), fauxtari(7).

Any good Atari 8-bit book: De Re Atari, The Atari BASIC Reference Manual, the OS Users' Guide, Mapping the Atari, etc.