Chengdu Ebyte Electronic Technology Co.,Ltd.
E22-400T22DC User
Manual
Copyright ©2012–2019
，
Chengdu Ebyte Electronic Technology Co.,Ltd.
3-7
3. Size and pin definition
No.
Name
Direction
Function
1
M0
Input
（
weak pull-up
）
Work with M1 to decide 4 working modes of module (not suspended, if not
used, could be grounded).
2
M1
Input
（
weak pull-up
）
Work with M0 to decide 4 working modes of module (not suspended, if not
used, could be grounded).
3
RXD
Input
TTL UART input, connects to external TXD output pin.
4
TXD
Output
TTL UART output, connects to external RXD input pin.
5
AUX
Output
To indicate module ’ s working status & wakes up the external MCU. During
the procedure of self-check initialization, the pin outputs low level.
