Chengdu Ebyte Electronic Technology Co.,Ltd. E22-400T22D User Manual
Copyright ©2012–2019,Chengdu Ebyte Electronic Technology Co.,Ltd. 3-6
3. Size and pin definition
Work with M1 to decide 4 working modes of module (not suspended, if not
used, could be grounded).
Work with M0 to decide 4 working modes of module (not suspended, if not
used, could be grounded).
TTL UART input, connects to external TXD output pin.
TTL UART output, connects to external RXD input pin.
To indicate module ’ s working status & wakes up the external MCU. During
the procedure of self-check initialization, the pin outputs low level.