User Manual
第
5
页 共
30
HLK-B35
9
GND
P
GND
10
NC
I/O
preserve
11
NC
I/O
preserve
12
IO20
I/O
preserve
13
IO21
I/O
WiFi connection
0: WiFi is not connected
1: WiFi is connected
14
IO22
I/O
TCP connection
0: Not connected to the TCP server
1: Connected to the TCP server
15
GND
P
GND
16
IO0
I/O
Module status indicator
17
IO8
I/O
Indicator light not used
18
IO1
I/O
preserve
19
IO3
I/O
Debug serial port (TX pin)
20
IO4
I/O
Debug serial port (RX pin)
21
RXD
I/O
Main serial port send pin
22
TXD
I/O
Main serial port Receive pin