User's Manual

Table Of Contents
SIM7090G User Manual V1.01
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3.3 UART Interface
SIM7090G can provide 3 channels serial ports: Main UART, Debug UART and GNSS UART interfaces.
Features of them are illustrated below:
The Main UART interface supports 0, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600,
115200, 230400, 921600, 2000000, 3000000, 3200000 and 3686400 bps. The rate 0bps marks
auto baud rate. And the default is 115200bps. It is used for data transmission and AT command
communication, and supports RTS and CTS hardware flow control. The default frame format is
8N1 (8 data bits, no parity, 1 stop bit).
The Debug UART interface supports a fixed baud rate of 115200bps, and is used for software
debugging and log output.
The GNSS UART interface supports 115200bps baud rate by default, and is used for GNSS data
and NMEA sentences output.
Table 10: Pin Definition of Main UART Interface
Pin Name
Pin No.
I/O
Description
Comment
DTR
62
DI
Data terminal ready. Sleep
mode control.
1.8V power domain
RXD
6
DI
Receive data
1.8V power domain
TXD
7
DO
Transmit data
1.8V power domain
CTS
39
DO
Clear to send
1.8V power domain
RTS
38
DI
Request to send
1.8V power domain
DCD
90
DO
Data carrier detection
1.8V power domain
RI
76
DO
Ring indication signal
1.8V power domain
Table 11: Pin Definition of Debug UART Interface
Pin Name
Pin No.
I/O
Description
Comment
DBG_RXD
61
DI
Receive data
1.8V power domain
DBG_TXD
60
DO
Transmit data
1.8V power domain
Table 12: Pin Definition of GNSS UART Interface
Pin Name
Pin No.
I/O
Description
Comment
GNSS_UART_RXD
61
DI
Receive data
1.8V power domain
GNSS_UART_TXD
60
DO
Transmit data
1.8V power domain