Thông số kỹ thuật:

No.	Item	Direction	Application
1	M0	Input（weak pull-up）	Work with M1 & decide the four operating modes. Floating is not allowed, can be ground.
2	M1	Input（weak pull-up）	Work with M0 & decide the four operating modes. Floating is not allowed, can be ground.
3	RXD	Input	TTL UART inputs, connects to external TXD (MCU, PC) output pin.Can be configured as open-drain or pull-up input
4	TXD	Output	TTL UART outputs, connects to external RXD (MCU, PC) input pin.Can be configured as open-drain or push-pull output
5	AUX	Output	To wake up the external MCU, during the procedure of self-check initialization, the pin outputs low level. Can be configured as open-drain output or push-pull output (floating is allowed).
6	VCC	Input	Power supply 2.3V-5.2V DC
7	GND	Input	Ground
8	Fixing hole	-	Fixing hole
9	Fixing hole	-	Fixing hole
10	Fixing hole	-	Fixing hole