BK Precision MDL4U Series, Руководство пользователя

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Operations 62
All SCPI commands are available through RS-232 programming. The EIA RS-232 standard defines the interconnections
between data terminal equipment (DTE) and data communications equipment (DCE). The electronic load is designed
to be a DTE and can be connected to another DTE such as a PC COM port through a null modem cable.
Note:
The RS-232 settings in your program must match the settings specified in the front panel System menu. Press
+ on the front panel to enter the System menu if you need to change the settings.
RS232 Data Format
The RS-232 data is a 10-bit word with one start bit and one stop bit.
Parity = None
Start Bit 8 Data Bits
Stop Bits
The number of start and stop bits are not programmable. However, the following parameters are selectable in the System
menu using the front panel + key.
Baud Rate
The System menu lets you select one of the following baud rates, which are stored in non-volatile memory: 4800, 9600,
19200, 38400, 57600, or 115200.
Parity
None - eight data bits without parity
Even - seven data bits with even parity
Odd - seven data bits with odd parity
RS232 Flow Control
The RS232 interface supports the following flow control options. For each case, the electronic load will send a maximum
of five characters after hold-off is asserted by the controller. The electronic load is capable of receiving as many as fifteen
additional characters after it asserts hold-off.
• CTS/RTS : The electronic load asserts its Request to Send (RTS) line to signal hold-off when its input buffer is
almost full, and it interprets its Clear to Send (CTS) line as a hold-off signal from the controller.
• XON/XOFF : When the input queue of the electronic load becomes more than ¾ full, the instrument issues an X-OFF
command. The control program should respond to this and stop sending characters until the electronic load issues
the X-ON, which it will do once its input buffer has dropped below half-full. The electronic load recognizes X_ON
and X_OFF sent from the controller. An X-OFF will cause the electronic load to stop outputting characters until it
sees an X-ON.
• NONE : No flow control.
Flow control options are stored in non-volatile memory.