User Interface; Display Interface; Keyboard Interface - Nokia 6720 Service Manual

RM-424; RM-564
System Module

User interface

Display interface

The following block diagram illustrates the display interface.
Display backlight is provided directly by EM ASIC.
Figure 59 Display interface

Keyboard interface

The following block diagram shows the keyboard interface. The keyboard interface is implemented with
RAPU's GENIOs. Keyboard GENIOs are protected from ESD with 10-channel ASIP Z4404 and 2-channel ASIP
Z4405.
RM-424 keyboard supports 3 keys multikeypress functionality.
The keypad LEDs are controlled by a separate LED driver. The driver is controlled by the I2C bus port 2 (adr.
0x33).
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