MKS ESP302-GPIB-ADPT, Руководство пользователя

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13 | ESP302-GPIB-ADPT
A1387A0-EDH0429En1010 11/21
USER's MANUAL
The ESP302-GPIB-ADPT has two operation modes: Data and Command.
•
In the Data mode, data passes transparently through the unit in both directions from the
GPIB bus to the serial interface. This mode is used to drive the ESP302 (see §
4.2 ).
•
In the Command mode, the ESP302-GPIB-ADPT operates as an IEEE-488.2 device and
the GPIB controller can access its internal parser which includes the IEEE-488.2 Common
Commands, the Status Reporting Structure and the SCPI configuration commands. This
mode is used for GPIB port configuration only (see §
3.5 )
The ESP302-GPIB-ADPT powers up in the Data mode and switches to the Command mode when sent
a GPIB Device Trigger (488.1 GET) command. Once in the Command mode, the unit will accept
configuration parameters, respond to queries, and save new configuration settings but
not transfer
serial data . The unit must be put back into the Data mode with the SYST:OPER DATA command or by
turning it off and back on before it can transfer serial data. Switching from Data to Command and back
to Data without power cycling does not affect the data held in the serial receive buffer.
In the Data mode, messages from the GPIB bus are placed in the serial transmit buffer and outputted
on the selected serial port. Serial characters are received in the serial receive buffer. When the
ESP302-GPIB-ADPT senses it had received a message, it is moved to the GPIB output buffer, freeing
the receive buffer for another message. If the ESP302-GPIB-ADPT is in the Command mode when it
receives a serial message, the serial message is held in the serial receive buffer until the module is
switched back to the Data mode.
Data flow on the ESP302-GPIB-ADPT's serial interface is always controlled by hardware handshake
lines. The module uses its 'clear-to-send' output signal to allow the serial device to send it data. When
the ESP302-GPIB-ADPT's serial receive buffer gets full, it drops its 'clear-to-send' output to stop the
serial device from sending any more data until there is space in the input buffer.
The ESP302-GPIB-ADPT's transmitter is normally enabled all the time to hold the serial line in the
mark (stop bit) state when it is not transmitting.
2.3 Protection of configuration parameters
All configuration parameters presented below are set in factory to match ESP302 features and are
locked with a password. Only GPIB address can be changed according to user need.
2.4 IEEE 488 Interface
2.4.1 Address Range
Primary addresses: 1 – 30 (default: 4) .
2.4.2 Data Buffers
GPIB input buffer - 4,096 bytes
Serial input buffer - 4,096 bytes