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Hardware Development Guide
ME3616
Figure 2-16 Schematic of 3-wire UART Connection
3.
4-wire UART connection, with hardware flow control:
TXD
RXD
RTS
CTS
DTR
DCD
RING
Serial Port
Serial Port
(DCE)
(DTE)
GND
GND
UART_TXD
UART_RXD
UART_RTS
UART_CTS
UART_DTR
UART_DCD
UART_RI
Figure 2-17 Schematic of 4-wire UART Connection
2.11.2.
UART
LEVEL
MATCH
Notice the level match when connect module to external MCU. Level must be less than 3.0V under normal
operation, and its default speed rate is 115200 bps.
We recommend to use Triode or IC for UART level match circuit. The pictures below are the recommended
level switch circuit for TXD, RXD, CTS, RTS. Each pin recommends two kinds of circuit, and you can select any one if
necessarily.