CityGrow CG102RS232, Руководство пользователя

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4. RS232 Serial Interface
The CG102RS232 provides standard DB9 female connector for connection with external system.
The pin assignment of the DB9 female connector is shown in Figure 2-1.
1
TXD
RXD
GND
RS232 female
6
2
3
4
5
7
8
9
Figure 4-1 Pin assignment of the DB9 female connector
The connection between CG102RS232 and the external system with 3 pins of the RS232 interface,
which are TXD, RXD and GND (Figure 2-2). The physical characteristics of the RS232 interface has
benn shown in Table 2-1.
External
System
ZBCA
TxD
TxD
RxD
RxD
GND GND
Figure 4-2 RS232 Interface connection between external system and CG102RS232
Table 4-1 Physical characteristics of the UART interface
PARAMETER MIN TYP MAX UNIT
Date Rate - 57,600 - bps
Framing 8N1
Hardware flow control Nil
Voltage Level of bit ‘0’ +5 12 15 V
Voltage Level of bit ‘1’ -15 12 -5 V
In the RS232 serial communication protocol, the sender is able to request the receiver to
acknowledge the sender. The timeout of the sender to received acknowledgment from receiver is
30ms. If the sender did not receive any acknowledgement from receiver within 30ms after
transmission, sender will retransmit the data frame again.