Cotek S1500-112, User Manual

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8-2. Interface Command :
The buffer size used for the RS232 port is 12-bytes. This unit will ignore
all bytes more than this value.
During transmission, this unit (inverter) will indicate it is ready to receive
data from computer by the 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.
8-2-1. The baud rate of the RS232 interface is determined by S5 and
S6 of DIP-SW, as shows in Appendix A.
Note: You have to reset the unit after adjustment to activate the
New settings.
8-2-2. Illustration of the RS232 operation:
8-2-2-1. RS232 command
Command format:
This unit uses high-level language commands with a
CR (0DH) and a 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.
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