Empty foot

Module ground wire

Empty foot

Empty foot

Empty foot

Empty foot

Empty foot

Module ground wire

Antenna interface (high-frequency signal output, 50 ohm characteristic impedance)

Module ground wire

Module ground wire

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Module ground wire

Module ground wire

Module ground wire

In conjunction with M1, it determines the module's four operating modes (it cannot be left floating; if not in use, it can be grounded).

In conjunction with M0, it determines the module's four operating modes (it cannot be left floating; if not in use, it can be grounded).

TTL serial port , connected to the external TXD output pin;

TTL serial port output, connected to the external RXD  pin;

Used to indicate the module's working status;

When the user wakes up the external MCU, it outputs a low level during the power-on self-test initialization period; (this level can be left floating).

Module power supply positive reference, voltage range: 2.3～5.5V DC

Module ground wire