Lcd Display Interface; Adc - SIM Tech SIM900D HD Manual

SIM900D Hardware Design
Table16: Pin description (Amphenol SIM card holder)
Pin Name Signal
SIM_VDD
C1
SIM_RST
C2
SIM_CLK
C3
GND
C5
VPP
C6
SIM_DATA
C7

3.12 LCD Display Interface

SIM900D provides a serial LCD display interface that supports serial communication with LCD device. When
used as LCD interface, the following table is the pin definition. LCD interface timing should be united with the
LCD device.
Table17: Pin Definition of the LCD interface
Pin Name
DISP_CLK
DISP_DATA
DISP_D/C
DISP_CS
*Note: This function is not supported in the default firmware. There must be some customized firmware if you
want. Please contact SIMCom for more details.
The DISP_RST can select the KBR0 or GPO0, in addition to the KBR0 or GPO0 there is no another function.

3.13 ADC

SIM900D provides one auxiliary ADC0 (General purpose analog to digital converter.) as voltage input pin, which
can be used to detect the values of some external items such as voltage, temperature etc. User can use AT
command "AT+CADC" to read the voltage value on ADC. For detail of this AT command, please refer to
document [1].
Table18: ADC specification
Voltage range
ADC Resolution
Sampling rate
SIM900D_HD_V1.02
Description
SIM Card Power supply, it can identify automatically the SIM Card power
mode，one is 3.0V±10%, another is 1.8V±10%. Current is about 10mA.
SIM Card Reset.
SIM Card Clock.
Connect to GND.
Not connect.
SIM Card data I/O.
Pin Number Function
13 Display clock for LCD
14 Display data output
16 Display data or command select
46 Display enable
MIN Type
0 -
- 10
- -
MAX
2.8
-
200K
46
Units
V
bits
Hz
09.04.2010