FT800 Series Programmer Guide
Version 2.1
Document Reference No.: BRT_000030 Clearance No.: BRT#037
147
Copyright © Bridgetek Limited
5.3
ROM and RAM Fonts
The graphics engine hardware draws bitmap graphics, and it is useful for software to
treat these graphics as fonts.
Font metrics - e.g. character height and width - are used by software when placing font
characters. For the ROM character bitmaps, these font metrics are in ROM. The co-
processor engine uses these metrics when drawing text in any of the 16 built-in ROM
fonts, numbered 16-31. Users can load similar font metrics into RAM, and hence create
additional user-defined fonts in bitmap handles 0-14. Bitmap handle 15 is reserved for
co-processor command CMD_Button/CMD_Keys/CMD_Gradient.
Each 148-byte font metric block has this format: