Installation Manual

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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 RS-232 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 RS-232 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 RS-232 Operation
6-3-1. RS-232 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.
6-3-2. Command format
This unit supports the following command format.
There should always be a CR (0DH) and a LF (0AH) appended to the command
while sending the command to this unit.