KEPCO BOP-ME 1KW, Руководство оператора

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BOP HIPWR 091719
3-65
Referring to Figure 3-21, when a command string is sent it must be terminated by a CR or LF
character. When the terminator character is received, the DSR line goes low and an optional
XOFF character is sent to the host. The XON XOFF protocol can be disabled by the user. When
disabled, the unit will not send XON XOFF characters via the serial port. XON XOFF characters
received by the unit will have no effect on serial transmission. The host must always be ready to
accept transmitted characters.
The commands are stored in a 256 byte FIFO (first in first out) buffer. Once a command string is
received, any additional characters are stored in the buffer while the BOP responds by transmit-
ting an XOFF character to the host requesting the host stop sending data. If more than 256
characters are received, the initial characters are lost; DSR stays low and XOFF is not transmit-
ted to the host until all data in the buffer is processed.
If a line terminator is received during the buffering period, as soon as the first command string is
complete, the next command string is processed.
When all commands have been received DSR goes high and an XOFF character is sent to the
host requesting the host not send data while the BOP is processing the commands received.
Once processing is complete, the unit sends XON repeatedly every five seconds if XON flow
control is enabled. NOTE: DSR can not be disabled.
If an ESC character is received, the buffers are cleared and all data is lost.
Note: When using DSR, most windows PC computers require that CTS be shorted to RTS
before the DSR line is connected.
FIGURE 3-21. RS 232 IMPLEMENTATION
Only seven control characters (characters between 00
H
and 1F
H
) are acknowledged by the
power supply:
• Carriage Return (CR, 0D
H
)
• Line Feed (LF, 0A
H
)
• Back Space (BS, 08
H
)
• Escape (ESC, 01B
H
)
• XON (011
H
)
• XOFF (013
H
)
• CAN (018
H
)