LGE Internal Use Only
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3.7 KEYPAD Interface
The keypad interface is connected to the X-Bus, together with the XBIU and the Shared Memory
Register, using a single Bus Interface.
The keypad supports two scan modes:
• By default, the keypad is a 4x6 scan matrix (4 input and 6 output pins).
• To set the keypad to a 5x5 scan matrix (5 input and 5 output pins)
The scan mode should be determined at the very beginning of the system start because changes are
not allowed later.
3. TECHNICAL BRIEF
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Figure 3-7 KEY MAXTRIX Interface
5
RIGHT
2
LEFT
#
8
SEL
MENU
KEY MATRIX
END
9
4
0
UP
3
DOWN
*
6
SEND
7
1
SW305
2V0_VRTC
SW304
SW317
SW307
SW302
SW306
SW308
SW318
SW316
SW303
SW315
SW312
SW319
SW320
SW313
SW301
SW309
SW311
SW310
SW314
KEY_IN3
KEY_OUT1
KEY_IN4
END_KEY
KEY_IN0
KEY_IN1
KEY_IN2
KEY_OUT4
KEY_OUT3
KEY_OUT2
Summary of Contents for KP105
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