UTR2810E Series LCR Meter
– User Manual
26
5. RS232 Serial Interface
In this chapter you will learn the following
：
Introduction of RS-232 interface
UTR2810E serial interface
Connect to computer
Serial port parameter
Key points of programming
The instrument uses an RS-232 interface (standard) to communicate with the computer for all instrument functions. Through
standard SCPI commands, user can also easily compile a variety of acquisition systems suitable for their own.
5.1 Introduction of RS-232C Interface
RS-
232 is the widely used serial communication standard, it’s also called asynchronous serial communication standard.
RS-232 is used to realize data communication between computers and peripherals. RS is an abbreviation for
"Recommended Standard", 232 is the standard number, this is a standard officially published by EIA in 1969, which
stipulates that one data line is transmitted one at a time.
The configuration of most serial ports is usually not strictly based on the RS-232 standard: 25 core connector are used on
each port (the current computer is basically use 9 core connector). The common RS-232 signal table see Table 5-1.
Signal
Symbol
Pin number of 25 core
connector
Pin number of 9 core
connector
Request to Send
RTS
4
7
Clear to Send
CTS
5
8
Data Set Ready
DSR
6
6
Data Carrier Detection
DCD
8
1
Data Terminal Ready
DTR
20
4
Transmitted Data
TXD
2
3
Received Data
RXD
3
2
GND
GND
7
5
Table 5-1 RS-232 Common Signal
5.2 UTR2810E Serial Interface
Serial ports of UTR2810E is not strictly based on the RS-232 standard
，
it’s just provide a smallest simplified subset, see
Table 5-2.
Table 5-2 UTR2810E Serial Signal
RS232C connector uses 9 core pin DB socket
，
sequence of pin see Figure 5-1
Figure 5-1 Back View of RS232C Connector
Signal
Symbol
Pin number of 9 core connector
Transmitted Data
TXD
3
Received Data
RXD
2
GND
GND
5
