ok, it "looks" like you are sending bitmaps for each character to the LCD when you want to display them, and you have bitmaps/fonts defined from 0-9 and degree and space, so if there is still room in memory you might be able to add character fonts to that ASCII_Large array and figure out how to map character values into it when processing a display string. The temp buffer is only good for 6 characters of course.
Did you write this or where did you find it?
I usually use PROGMEM for "large" tables FYI, so that they don't soak up a bunch of RAM. i.e.
//creating the custom fonts:
LcdCommandWrite(0b01001000); // set cgram
static byte chars[] PROGMEM = {
0b11111, 0b00000, 0b11111, 0b11111, 0b00000,
0b11111, 0b00000, 0b11111, 0b11111, 0b00000,
0b00000, 0b00000, 0b00000, 0b11111, 0b00000,
0b00000, 0b00000, 0b00000, 0b11111, 0b00000,
0b00000, 0b00000, 0b00000, 0b11111, 0b00000,
0b00000, 0b00000, 0b00000, 0b11111, 0b01110,
0b00000, 0b11111, 0b11111, 0b11111, 0b01110,
0b00000, 0b11111, 0b11111, 0b11111, 0b01110 };
also using binary notation can allow you to visualize the font in the code sort-of. Here we have 5 8x5 characters. A thick line on top, a thick line on bottom, a thick line on top and bottom, a completely filled font, and a dot.
from:
http://opengauge.googlecode.com/svn/...no/mpguino.cpp