LPWA Module Series
BG950A-GL&BG951A-GL_Hardware_Design
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4.3. UART Interfaces
BG950A-GL/BG951A-GL module provides four UART interfaces and the following shows their features:
Main UART:
It supports 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600 and 3000000 bps baud
rates, and the default baud rate is 115200 bps. It is used for AT command communication and data
transmission, and supports RTS and CTS hardware flow control. The default frame format is 8N1 (8
data bits, no parity, 1 stop bit).
CLI UART:
It supports 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600 and 3000000 bps baud
rates, and the default baud rate is 115200 bps. It is used for firmware upgrade, software debugging,
log output, GNSS data and NMEA sentences output, and supports RTS and CTS hardware flow
control. The default frame format is 8N1 (8 data bits, no parity, 1 stop bit).
Debug UART:
It supports 921600 bps baud rate by default, and is used for RF calibration and log output, and
supports RTS and CTS hardware flow control. The default frame format is 8N1 (8 data bits, no parity,
1 stop bit).
CLI/GNSS UART:
For BG950A-GL module, this interface can only be used as CLI UART interface. And pin 27 and pin
28 should be connected to pin 95 and pin 94 respectively inside the module. For BG951A-GL module,
this interface can only be used as GNSS UART interface. The GNSS UART interface supports
115200 bps baud rate by default, and it is used for GNSS data and NMEA sentences output.
The following tables show the pin definition of four UART interfaces.
Table 14: Pin Definition of Main UART Interface
Pin Name
Pin No. I/O
Description
Comment
MAIN_DTR
30
DI
Main UART data terminal ready
1.8 V power domain
If these pins are unused,
keep them open.
MAIN_RXD
34
DI
Main UART receive
MAIN_TXD
35
DO
Main UART transmit
MAIN_CTS
36
DO
DTE clear to send signal from DCE
(Connect to DTE’s RTS)
MAIN_RTS
37
DI
DTE request to send signal from
DCE (Connect to DTE’s RTS)
MAIN_DCD
38
DO
Main UART data carrier detect
MAIN_RI
39
DO
Main UART ring indication
