NB-IoT Module Series
BC66 Hardware Design
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Debug UART Port:
TXD_DBG: Send data to RXD of DTE.
RXD_DBG: Receive data from TXD of DTE.
Auxiliary UART Port:
TXD_AUX: Send data to the RXD of DTE.
RXD_AUX: Receive data from the TXD of DTE.
Ringing Signal:
RI: Ring indicator (when there is a SMS or URC output, the module will inform DTE with the RI* pin).
For more details, please refer to
Chapter 3.12
.
Table 9: Pin Definition of UART Interfaces
“*” means under development.
3.8.1. Main UART Port
The main UART port is used for AT command communication and data transmission. It can also be used
for firmware upgrading. The default baud rate is 115200bps.
The figure below is a schematic diagram of the connection between DCE (the module) and DTE.
Interface
Pin Name
Pin No.
Description
Comment
Main UART Port
TXD
17
Transmit data
1.8V power domain
RXD
18
Receive data
Debug UART Port
RXD_DBG
38
Receive data
TXD_DBG
39
Transmit data
Auxiliary UART Port
RXD_AUX
28
Receive data
TXD_AUX
29
Transmit data
Ringing Signal
RI*
20
Ring indicator
NOTE