ra8806 RAIO Technology Inc., ra8806 Datasheet - Page 66

• Manufacturer Part Number: ra8806
• Description: Two Layers Character/graphic Lcd Controller
• Manufacturer: RAIO Technology Inc.

Preliminary Version 1.2
RAiO
TECHNOLOGY INC.
XCLK
LP
Memory Write Busy:
Following two conditions will cause the Memory write busy:
It will cause the DDRAM lost when accessing DDRAM in the period of Memory Write Busy. So user
must check the busy status after the upper two conditions is done.
Besides, RA8806 provide polarity setting for “BUSY” and interrupt “INT” pin. (Please refer to register
MISC)
Normally, this “BUSY” pin is connected to MPU I/O input, and then MPU have to monitor this pin
before accessing RA8806. The following is the timing of BUSY pin. The BUSY can be active high or
low that depend on the setting of REG[01h] Bit-5.
1. When MPU write data in text-mode. Depending on different size of font, it needs an enough
2. When MPU program RA8806 as a memory clear function(FNCR Bit-3 = 1). The period of
time to write the font to DDRAM. At the period, RA8806 can’t access the DDRAM again, it’s
a memory write busy condition.
clear DDRAM also cause a memory write busy.
MCU
ITCR
Figure 6-35 : Scan for Each COM Line
Memory-Write
Figure 6-34 : Data Flow of DDRAM
RA8806
Data RAM
Controller
Interface
Display
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T_COM
Two Layers Character/Graphic LCD Controller
LCD-Scan
COM_SCAN
Driver
LCD
www.raio.com.tw
RA8806