Initial commit

README.md

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+# Intro
+
+Mobitec flip-disc displays use MC27C1001 EPROM-s to store the
+firmware (?) and fonts.
+In the `firmware/` directory you can find two ROM dumps.
+
+# Useful commands
+
+To extract font sections:
+
+```
+dd if=mobitec-1682-r7-bib-01979-r3.bin of=mobitec-1682-r7-bib-01979-r3-fonts.bin skip=64 bs=1024
+dd if=mobitec-01682-r7-bib-01369-r9.bin of=mobitec-01682-r7-bib-01369-r9-fonts.bin skip=64 bs=1024
+```
+
+For diffing font sections:
+
+```
+dhex mobitec-1682-r7-bib-01979-r3-fonts.bin mobitec-01682-r7-bib-01369-r9-fonts.bin
+```
+
+# Dump structure
+
+The firmware seems to be located in the first 7KiB and the font data
+starts at 0x10000 offset.
+
+The font beginning marker seem to consist of a character from `a` to `z`
+followed by at least 60 null characters.
+They don't seem aligned or indexed in any way so easiest is just to scan
+for known markers.
+
+After the beginning marker you can find the lookup table which maps
+printable ASCII characters to a glyph address.
+The lookup table is 190 bytes (95x 16-bit addresses) which correspond
+to ASCII characters 32 up to 126.
+Not all fonts include all characters, missing glyphs are represented by address 0.
+Note that the glyph address is relative to the beginning of font structure,
+beginning marker inclusive.
+
+At the glyph address first width and height of the glyph are found represented
+by two 8-bit integers. The actual bitmap data follows in 8x8 pixel tiles
+packed together as 8 bytes.
+
+