Table 7: Logic Levels Of The Uart Interfaces - Quectel M35 User Manual

The logic levels are described in the following table.

Table 7: Logic Levels of the UART Interfaces

Parameter
V
IL
V
IH
V
OL
V
OH
Table 8: Pin Definition of the UART Interfaces
Interfaces Pin No.
14
Debug Port
15
20
21
22
UART Port 23
24
25
26
NOTE
1) DTR pin can be used as SIM1_PRESENCE pin via ―AT+QSIMDET‖ command.
1.
2)
2. When using the SIM2 interface, DCD pin can be used as SIM2_RST pin. For more details, please
refer to the document [6].
3)
3. When using the PCM interface, RI pin can be used as PCM_CLK.
M35_User_Manual
Min.
0
0.75×VDD_EXT
0
0.85×VDD_EXT
Pin Name
DBG_RXD
DBG_TXD
1)
DTR
RXD
TXD
CTS
RTS
2)
DCD
3)
RI
Confidential / Released
Max.
0.25×VDD_EXT
VDD_EXT +0.2
0.15×VDD_EXT
VDD_EXT
Description
Receive data
Transmit data
Data terminal ready
Receive data
Transmit data
Clear to send
Request to send
Data carrier detection
Ring indication
GSM/GPRS Module Series
M35 User Manual
Unit
V
V
V
V
Alternate Function
SIM1_PRESENCE
SIM2_RST
PCM_CLK
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