Chengdu Ebyte Electronic Technology Co., Ltd.
E22-400T30S_User Manual _EN
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
7
Chapter 3 Mechanical Dimensions and Pin Definitions
Pin Number
Pin
Name
Pin Direction
Pin Usage
1
M0
Input (very weak pull-up)
Cooperate with M1 to determine the 4 working modes of the module (not
floating, if not used, it can be grounded)
2
M1
Input (very weak pull-up)
Cooperate with M0 to determine the 4 working modes of the module (not
floating, if not used, it can be grounded)
3
RXD
Input
TTL serial port input, connected to the external TXD output pin;
4
TXD
Output
TTL serial port output, connected to external RXD input pin;
5
AUX
Output
Used to indicate the working status of the module; the user wakes up
the external MCU, and outputs a low level during the initialization of
the power-on self-test; (can be suspended)
6
VCC
Input
Module power positive reference, voltage range: 3.3 ~ 5.5V DC
7
GND
Input
Module ground
8
C2CK
Input
Clock pin when the program is loaded (dangling, users do not need to connect)
9
GND
Input
The ground pin when the program is loaded (dangling, the user does not need
to connect)
