User's Manual

6. Serial Interface and Debug Interface
The TXD and RXD pins should be connected to host MCU. The DTR pin should be controlled to
trigger SLEEP mode or wakeup the module. The RTS and CTS pins should be connected to the
host MCU if hardware flow control is required.
The TXD, RXD, PWRKEY and GND pins can also be used for software upgrade and high-level
acoustic parameters configuration. The DBG_TXD and DBG_RXD pins are only used for
software debug. Please note that the PWRKEY pin should be pulled to low level when the M10 is
being upgraded. For more detailed information on serial port design, please refer to document [2]
Notes: It’s recommended to connect the pins necessary for firmware upgrade to external interface.