3. TECHNICAL BRIEF
- 42 -
3. 9 Keypad Switches and Scanning
The key switches are metal domes, which make contact between two concentric pads on the
keypad layer of the PCB when pressed. There are 24 switches (SW1-SW2,KB2~KB22),
connected in a matrix of 5 rows by 5 columns, as shown in Figure, except for the power switch
(KB101), which is connected independently. Functions, the row and column lines of the keypad
are connected to ports of AD6525. The columns are outputs, while the rows are inputs and have
pull-up resistors built in.
When a key is pressed, the corresponding row and column are connected together, causing the
row input to go low and generate an interrupt. The columns/rows are then scanned by AD6525
to identify the pressed key.
Figure 3-23. C1150 KEYPAD CIRCUIT
PWR KEY
KEYON
R107
10K
VBAT
KB101
R110
1K
1
6
SELECT
0
DOWN
LEFT
DOWN
UP
5
2
RIGHT
8
9
SEND
7
CLR
3
CONFIRM
*
UP
MENU
4
#
SP232
KB17
AVL5M02-200
VA202
SP235
SP228
SP201
SP230
SP205
SP233
KB20
KB16
AVL5M02-200
VA201
KB19
KB5
SP234
SP204
SP212
KB6
KB10
KB7
KB14
KB3
KB8
SP231
KB15
R224
680
SP210
KB11
SP209
SP208
SP229
SP211
SP227
SP213
SP206
KB21
KB2
KB4
SP207
R225
680
1
2
3
4
5
SW2
R241
680
R240
680
R229
680
R228
680
KB12
KB18
KB13
KB9
KB22
SW1
1
2
3
4
5
SP226
KEY_ROW0
KEY_COL2
KEY_ROW1
KEY_COL0
KEY_COL1
KEY_COL3
KEY_COL4
KEY_ROW2
KEY_ROW3
KEY_ROW4
Содержание C1150
Страница 1: ...Service Manual Model C1150 Service Manual C1150 Date October 2005 Issue 1 0 ...
Страница 3: ......
Страница 94: ...5 DOWNLOAD AND CALIBRATION 95 11 Wait until Sending Block is completed 1 Wait Until Sending Block is completed ...
Страница 99: ...Note 100 ...
Страница 104: ... 105 8 PCB LAYOUT 8 PCB LAYOUT ...
Страница 105: ... 106 8 PCB LAYOUT ...
Страница 113: ...10 STAND ALONE TEST 114 Figure 10 2 HW test setting Figure 10 3 Ramping profile ...
Страница 117: ...Note 118 ...
Страница 119: ... 120 Note ...
Страница 135: ...Note 136 ...