Writing To Display Memory (Vram) - Fujitsu MB91319 Series Hardware Manual

18.2.7

Writing to Display Memory (VRAM)

The OSDC command is set at OSDC control addresses 00
memory.
• Writing a single character to character RAM
• Writing multiple characters to character RAM collectively
• Writing to line RAM
■ Writing to Display Memory
The OSDC command is issued to OSDC control addresses 00H to 08H for writing to display
memory.
■ Writing a Single Character to Character RAM
Use the following commands to write data on an arbitrary character to an arbitrary address in
character RAM:
Figure 18.2-12 shows the procedure for writing to character RAM.
VRAM write address set (Command 0)
Character data set 1 (Command 1)
Character data set 2 (Command 2)
*1: When writing to consecutive addresses continuously, you can omit this command for the latter
character RAM write.
*2: You can also omit this command if the current character data is the same as the one set by the
preceding "character data set 1" command.
Figure 18.2-12 Procedure for Writing to Character RAM
to 08
H H
*1
Set the row and column addresses
*2
Write the character data to character
RAM. The VRAM write address is
then incremented.
CHAPTER 18 OSDC
for writing to display
477