Phytec phyCORE-OMAP44 Series, Руководство по оборудованию

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phyCORE-OMAP44xx Part II: PCM-959/phyCORE-OMAP44xx Carrier Board
L-760e_1 © PHYTEC Messtechnik GmbH 2012 143
6 X_KPD_ROW1 I 1.8 V Keyboard row 1
7 X_KPD_COL2 O VCC_1V8_IO Keyboard column 2 (open drain)
8 X_KPD_ROW2 I 1.8 V Keyboard row 2
9 X_KPD_COL3 O VCC_1V8_IO Keyboard column 3 (open drain)
10 X_KPD_ROW3 I 1.8 V Keyboard row 3
11 X_KPD_COL4_CSI21_DX3 O/I VCC_1V8_IO / CSI Keyboard column 4 (open drain)
/ CSI2-A (CSI21) differential
data lane positive input 3
(see note below)
12 X_KPD_ROW4_CSI21_DY3 I 1.8 V / CSI Keyboard row 4 / CSI2-A (CSI21)
differential data lane negative
input 3 (see note below)
13 X_KPD_COL5_CSI21_DX4 O/I VCC_1V8_IO / CSI Keyboard column 5 (open drain)
/ CSI2-A (CSI21) differential
data lane positive input 4
(see note below)
14 X_KPD_ROW5_CSI21_DY4 I 1.8 V / CSI Keyboard row 5 / CSI2-A (CSI21)
differential data lane negative
input 4 (see note below)
15, 16 GND - - Ground
Note:
Contacts 10 to 13 of the keypad connector provide either signals of the keyboard interface, or camera lanes 3
and 4 of the primary camera interface. The resistor array JN1 on the phyCORE-OMAP44xx allows to choose
which signals are brought out at these pins. The default setting of JN1 at position 1 allows to use the keyboard
interface without changes. Please refer to
Table 6 for more information on JN1.
Caution:
When using the keypad connector (X21) with a smaller keypad (for example, 4 × 4), unused rows must be tied
high (e.g. by connecting the corresponding pins to contact 1 (VCC_1V8_IO) of connector X21) to prevent
disturbing the scanning process. Normally, all rows must be pulled up internally at the I/O cells of the device.
Location Signal I/O SL Description
Table 69: Keypad Connector (X21) Signal Mapping