SIM300D EVB User Guide
SIM300D-EVB_UGD_V1.01 Page 13 of 19
4. Test Interface
Figure
10:
Test
interface
overview
4.1 Serial Interface
J1---RS232 Interface
Figure
11:
J1
Interface
RS232 Interface Pin List:
Pin
Signal
I/O
Description
1 TXD O
Transmit data
2 RXD
I
Receive data
3 DCD O
Data carrier detection
4 RI O
Ring Indicator
5 CTS O
Clear to Send
6 GND
GND
7 DTR
I
Data Terminal Ready
8 DEBUG_RX
I
Receive
data
9 RTS
I
Request to Send
10 DEBUG_TX
O
Transmit
data
