CH9720 Programmable DC Electronic Load Instructions Appendix B
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TXD(2) (3) RXD
RXD(3) (2) TXD
GND(5) (5) GND
RS232C Parameter
Transfer method
Full-duplex asynchronous communication with start and stop bits
Baud rate
1200bps
，
9600bps
，
19200bps
，
38400bps
，
115200bps
Data bit
8 BIT
Stop bit
1 BIT
Check
No
Terminator
CR, LF, CR+LF optional
Contact method
Software contact
Connector
DB9 core
B2 USB remote control system
USB communication is one of widely-used way.
USB Bus
USB (Universal Serial Bus) remote control system controls the instrument through the USB
interface. This connection conforms to USBTMC-USB488 and USB2.0 protocols.
USB-CDC(Communication), the tester is considered as COM
（
Vcom
）
，
which can realize the
same communication way as RS232C
USB-TMC
（
Test&measurement
）
, the protocol is based on USB to realize the communication
with USB device by means of GPIB.
USB Configuration
USB-DEVICE adopts USB-B type connector
，
USB cable is USB A-B type
：
After connecting the instrument to PC through USB, according to the USB
communication mode, different drivers need to be installed on the PC before using it.
PC
(Controller)
CH9720X
instrumen
t
To PC
To Tester