W2000A Screenshot Patch against FW1.2.BF-0.75beta Firmware
==========================================================
--- Version 0.2 ---

Changelog
---------

* v0.1 (Initial Release):

  Provides new RS232 command # (pound) to initiate b/w screendump with simple
  RLE compression.  Usually only around 10-15kB to be transferred.

* v0.2:

  Additional ' (tick) command to initiate full plane dump with same simple RLE
  compression as with the # command.  Around 60-65kB total to be transferred.

  Planes are coloured and combined into an PPM image file.  Individual planes
  are also available as numbered PGM image files for inspection or partial
  export.

  New -h and -f command line options.  More status and progress messages on
  stderr.

  Since multiple planes can be output, data is written to file(s) in v0.2, no
  longer to stdout.  Use -f option to specify target file prefix.

DSO Preperation
---------------

  Patch and compile firmware with included .diff or use precompiled TomCat.ram.
  Upload firmware (i.e., with GERMSloader.pl).

Building
--------

  $ make w2000a-screenshot

  or if your make(1) isn't clever enough to work without a Makefile:
  $ cc w2000a-screenshot.c -o w2000a-screenshot

Setup Serial Device
-------------------

  $ stty -F $device 115200 raw
  (stty -f for *BSD usually)

Making A Screenshot
-------------------

  (1) Start w2000a-screenshot:

        $ ./w2000a-screenshot < $device

  (2) Initiate screendump by executing # or ' command on RS232:

        $ echo '#' > $device
        $ echo "'" > $device

  (3) The utility decompresses the RLE data from the DSO to PPM files
      and colours and combines the retrieved planes to a single PGM image file.

      You might want to use ppmto*/pgmto*(1) of NetPBM or convert(1) of
      ImageMagick to make more handy files out of the PPM/PGM images, i.e.:

        $ convert screenshot.pgm screenshot.png

