Chengdu Ebyte Electronic Technology Co., Ltd.
E220-900T30D User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co.,Ltd.
6
3. Size and Pin Definition
Figure 3-1 Mechanical size and pin definition
Table 3-1 Pin definition table
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 inputs, connects to external TXD output pin.
4
TXD
Output
TTL UART outputs, connects 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 low level during power-on self-check
initialization; (can be left floating)
6
VCC
Input
Voltage range: 3.0
～
5.5V DC
7
GND
Input
Ground
8
Fixed hole
-
Fixed hole
9
Fixed hole
-
Fixed hole
10
Fixed hole
-
Fixed hole
11
Fixed hole
-
Fixed hole
