RA8835A
Version 1.0
Dot Matrix LCD Controller
7-15 CG Memory Allocation
Since the RA8835A series uses 8-bit character codes, it can handle no more than 256 characters at a
time. However, if a wider range of characters is required, character generator memory can be bank-
switched using the CGRAM ADR command.
Figure 7-27: Internal and External Character Mapping
Note that there can be no more than 64 characters per bank.
Table-21: Character Mapping
Item
Internal/external character generator
selection
Parameter
Remarks
M0
1 to 8 pixels
9 to 16 pixels
Greater than 16 pixels
M2 = 0
M2 = 1
Character field
height
Graphics mode (8 bits ´1 line)
Internal CG ROM/RAM select
External CG ROM/RAM select
CG RAM bit 6 correction
Determined by the character
code
Automatic
M1
Can be moved anywhere in
the display memory address
space
Specified with CG RAM ADR
command
CG RAM data storage address
Other than the area of Figure
7-2A
External CG
ROM
Address
192 characters or less
More than 192
characters
Set SAG to F000H and overly
SAG and the CG ROM table
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