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8-7-3. Using the RS-232C interface
You may use the serial port of your Personal computer or sequencer for
communication through the RS-232C interface. The RS-232C interface utilizes
the CTS-RTS flow for communication control. If the flow control fails to work
properly, some characters may be lost, resulting in malfunctioning. Please note
this. Note that the cross cables for Personal computers use different flow control
connection and are unusable.
8-7-4. Using the local bus
The time-out of communication between the Personal computer and master unit
should be longer when the local bus is used. The communication time is
influenced by the cable length. Check it and determine the time-out value.
General description about communication
When you are going to control several PSF Series power
supply units from a Personal computer, the potential of
the frames of the power supply units must be equal to
that of the Personal computer frame. If those potentials
are different, you may receive electric shocks or the
Personal computer may be broken. Be very careful.
8-8. Communication commands
・
Every communication command consists of general alphanumeric characters
and symbols and has a header, which is the abbreviation of a function.
Parameters consist of an integer (NR1) and decimal places (NR2).
Parameters following the tenth character are ignored. Decimal places are
rounded off according to the actual setting resolution. The response
contains no header. Only parameters are sent in response.
・
LF (0
×
0A) is used as the delimiter, which indicates the end of data.
Multi-commands consisting of several continuous commands are not applicable
to communication of the PSF Series power supply unit. Thus, commands must
be separated with delimiters. If delimiters are used, the interface unit
automatically controls the flow of communication. Communication commands
are accepted, whether they are written in capital letters or small letters.
・
Use the address command “:ADDR” to specify a system address of the
slave unit when communicating with the slave unit in the local bus from the
Personal computer. Since address 1 has been set by default, the system
address of the master unit is to be specified.
・
An error occurs if a command causing a competitive operation is sent while
the sequence or external control function is working.
