Redwood Shores, 2 april 2008.

Dear Doug,

As said, you CAN use this system to read from the flash program memory. So
you could store your font in the flash program memory. Given that you want a
font of 5x7, this means you can store two vertical lines of a font in one
location, so you would use 3 locations per character. For encoding 96
characters, this means you will need 288 memory locations, leaving you with
plenty of space to store your application. I would recommend this solution,
although it makes it impossible to change the characters on the fly.

If you insist on using the EEPROM, without compressing you could fit 51
characters in it (5 bytes/character). Using proportional fonts you could
probably fit all necessary characters in it (my initial calculation suggests
85, but it is probably even higher). Problem with proportional fonts is the
fact that you can't calculate where characters start in your EEPROM, so
you'll have to read through the entire ROM to find the character to display,
or create an index, which will waste RAM. You could use the 8th bit to
indicate the end of a proportional character. So 'I' would be stored as 191,
'a' as 50, 42, 188. There are obviously many other ways, though for a
graphic LCD proportional can look very nice.

Greetings,
Maarten Hofman.
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