SIM340 Hardware Design
3.12 LCD display interface
SIM340 provides a serial LCD display interface that supports serial communication with
LCD device. These are composite pins that can be used as GPIO ports or LCD display
interface according to your application. When used as LCD interface, the following table is
the pin definition. LCD interface timing should be united with the LCD device.
Table
18
: Pin definition of the LCD interface
Name
Pin
Function
DISP_DATA
18
Display data output
DISP_CLK
20
Display clock for LCD
DISP_CS
22
Display enable
DISP_D/C
24
Display data or command select
DISP_RST
26
LCD reset
Note: This function is not supported in the default firmware. There must be special firmware if
you want. Please contact SIMCom for more details.
3.13 Keypad interface
The keypad interface consists of 5 keypad column outputs and 5 keypad row inputs. The basic
configuration is 5 keypad columns and 5 keypad rows, giving 25 keys, plus the 5 additional keys
(i.e. where a keypad row is pulled low regardless of which column is enabled).
Table
19
: Pin definition of the keypad interface
Name
Pin
Function
KBC0
27
KBC1
29
KBC2
31
KBC3
33
KBC4
35
Keypad matrix column
KBR0
37
KBR1
39
KBR2
41
KBR3
43
KBR4
45
Keypad matrix row
The keypad interface allows a direct external matrix connection. A typical recommended circuit
SIM340_HD_V3.09
18.03.2009
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