Samlex America SR1000-148 - Manual (Page 27)

SR Series Inverter
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6-1-3. The RS232 interface of this unit employs ASCII code to implement the
asynchronous serial transmission control.
The byte structure is START-BIP – 8 BIT DATA-STOP BIT.
Baud rate: 1200/2400/4800/9600(See details in Section 5-3-1).
6-1-4. Coupled with PC software application port. Operation is as detailed in
Section 6-2.
6-2. Interface Commands:
The buffer size used for the RS232 port is 12-byte. This unit will ignore all bytes
more than this value. During transmission, this unit will indicate it is ready to
receive data from computer by this DTR line. A computer has to check the DTR
line before sending any information to this unit. This unit is normally always
ready to receive data while operating. When a LF character (ASCII code 0AH)
is received, this unit would finish the receiving by clearing the DTR status and
begin to interpret the received information. The unit would execute the received
command (AND/OR data) if it is correct. Irrespective of whether the command is
accepted or not, the unit will always send back a response signal to the
computer and set DTR to ready for receiving more incoming information.
6-2-1. The Baud-rate of the RS232 interface can be set with the help of the Setup
Menu (See details in Section 5-3-1).
Note. You have to reset the unit after adjustment to activate the new setting.
6-3. Example of the RS232 Operation:
6-3-1. RS232 command:
Command format:
This unit uses high-level language commands with a CR (0DH) and
LF (0AH) as the end of the command.
The system would interpret and execute the command only after these two
characters are received. After the unit execute the command, it would send
a response string to the computer. The response string is as follows:
= > CR LF: Command executed successfully
? > CR LF: Command error, not accepted
! > CR LF: Command correct but execution error (e.g. parameters out of
range).
If the command needs any information from the unit, the unit would send
the information back to the computer (with CR and LF) and then send the
response string to the computer.