20
8. Appendix B
8-1. Operations of RS232 Serial Port
8-1-1. Hardware design
：
This unit uses a 9-pin D connector and three of RS232 signal lines
：
RECEIVE DATA (RXD)
：
PIN2
TRANSMIT DATA (TXD)
：
PIN3
DATA TERMINAL READY (DTR)
：
PIN4
8-1-2. The connection between this unit and a computer is as follows
：
Computer
Power Inverter
RXD
RXD
TXD
TXD
DSR
DTR
RTS
CTS
GND
GND
8-1-3. The RS232 interface of this unit employs ASCll code to implement the
asynchronous serial transmission control.
The byte structure is START BIP – 8 BIT DATA-STOP BIT Baud
rate
：
1200,2400,4800,(SET BY DIP-SW).
Parity check
：
NONE, not settable
Data bit
：
8, not settable.
Stop bit
：
1, not settable.
