Gpib Ieee Std. 488.2 Error Handling; Gpib Parallel Poll - Promax GR-205 Manuel D'instructions

USER'S MANUAL. GR-205
Controller
Electrical Interface

5.4.2 GPIB IEEE Std. 488.2 Error Handling

The IEEE 488.2 UNTERMINATED error (addressed to talk with nothing to say)
is handled as follows. If the instrument is addressed to talk and the response formatter
is inactive and the input queue is empty then the UNTERMINATED error is generated.
This will cause the Query Error bit to be set in the Standard Event Status Register, a
value of 3 to be placed in the Query Error Register and the parser to be reset. See the
Status Reporting section for further information.
The IEEE 488.2 INTERRUPTED error is handled as follows. If the response
formatter is waiting to send a response message and a <PROGRAM MESSAGE
TERMINATOR> has been read by the parser or the input queue contains more than
one END message then the instrument has been INTERRUPTED and an error is
generated. This will cause the Query Error bit to be set in the Standard Event Status
Register, a value of 1 to be placed in the Query Error Register and the response
formatter to be reset thus clearing the output queue. The parser will then start parsing
the next <PROGRAM MESSAGE UNIT> from the input queue. See the Status
Reporting section for further information.
The IEEE 488.2 DEADLOCK error is handled as follows. If the response
formatter is waiting to send a response message and the input queue becomes full
then the instrument enters the DEADLOCK state and an error is generated. This will
cause the Query Error bit to be set in the Standard Event Status Register, a value of 2
to be placed in the Query Error Register and the response formatter to be reset thus
clearing the output queue. The parser will then start parsing the next <PROGRAM
MESSAGE UNIT> from the input queue. See the Status Reporting section for further
information.

5.4.3 GPIB Parallel Poll

Complete parallel poll capabilities are offered on this generator. The Parallel
Poll Enable Register is set to specify which bits in the Status Byte Register are to be
used to form the ist local message The Parallel Poll Enable Register is set by the *PRE
<nrf> command and read by the *PRE? command. The value in the Parallel Poll
Enable Register is ANDed with the Status Byte Register; if the result is zero then the
value of ist is 0 otherwise the value of ist is 1.
The instrument must also be configured so that the value of ist can be returned
to the controller during a parallel poll operation. The instrument is configured by the
controller sending a Parallel Poll Configure command (PPC) followed by a Parallel Poll
Enable command (PPE). The bits in the PPE command are shown below:
bit 7 =
bit 6 =
bit 5 =
bit 4 =
09/2004
C0
E2
X Don't care
1
1 Parallel poll enable
0
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