User guide

M80 EVB User Guide
M80_EVB_UGD_V1.2 - 25 -
Figure 24: Pins of main UART
Table 9: Pins of Serial port
Pin
Signal
I/O
Description
Note
1
DCD
O
Data carrier detection
2
TXD
O
Transmit data
3
RXD
I
Receive data
4
DTR
I
Data terminal ready
5
GND
Ground
7
RTS
I
Request to send
8
CTS
O
Clear to send
9
RI
O
Ring indicator
Note: The above pins are RS232 voltage level.
The CMOS level of UART signal can be test through test points below. Customer can use these
test points to verify the design between customer device and the module.
1
2
3
4
5
9
8
7
Quectel
Confidential