KEPCO KLP SERIES, Руководство оператора

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KLP073008
3-15
• Baud rate: 9600
• Parity: None
• Data Bits 8
• Stop Bits 1
• Echo OFF
• XON ON (enabled) NOTE: Kepco strongly recommends the XON XOFF method
for data transfer via RS 232 protocol for all Kepco products. If this method is
not selected, it is the user's responsibility to ensure completion of any
response by the power supply prior to issuance of subsequent commands.
3.4.1 SERIAL INTERFACE
The serial interface behaves like the GPIB interface in that the command is parsed after receiv-
ing a control character of either a Line Feed or Carriage Return. The serial interface supports six
special control characters. The six special control characters are:
Escape (1B
H
) Causes the input buffer to be cleared. This character is used to ensure
that the buffer is empty when the host powers on since it is possible
that the KLP Power Supply was previously powered on and received
some characters prior to the initialization of the host computer.
Backspace (08
H
) Causes the last character in the input buffer to be removed from the
input buffer queue.
Carriage Return (0D
H
) Causes the input buffer to be parsed by the KLP Power Supply.
Line Feed (0A
H
) Causes the input buffer to be parsed by the KLP Power Supply.
> (3E
H
) and < (3C
H
) The > character turns on the echo mode upon receipt of the character.
The < character turns off the echo mode. The message “echo off“ or
“echo on“ will be displayed to confirm this.
3.4.2 RS 232 IMPLEMENTATION
The following paragraphs are provided to help the user understand how the RS 232 serial inter-
face is implemented in the KLP Power Supply. Since the RS 232 protocol does not use a parity
bit, the echo mode is the default method used to ensure reliable communication between the
command originator (computer) and the KLP Power Supply, thus avoiding a more complex
“handshake” protocol.
Upon initial application of source power to the KLP input, or after restoration of source power fol-
lowing an interruption, the power supply will return the identification string described in Appen-
dix A, PAR. A.6, to the host controller. This indicates that the KLP is initialized and ready to
accept programming commands.
When the KLP Power Supply is in the RS 232 echo mode it returns all data received from the
host controller. The KLP Power Supply provides two additional options that allow handshake
communication: the Prompt method and the XON XOFF method. In standard echo mode the
controller must verify that each character is echoed back by the KLP. As shown in Figure 3-1,
there are times when the KLP does not echo back the character from the controller, requiring
that the controller resend the character. By using the handshake options (prompt and XON