Tabor 8020, Руководство пользователя

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The Service Request Enable Register is read with
the *SRE? common query. The response to this
query is an number that represents the sum of the
binary-weighted value of the Service Request Enable
Register. The value of the unused bit 6 is always
zero.
The Service Request Enable Register is written
using the *SRE common command followed by a
<Decimal Numeric Program Data> element repre-
senting the bit values of the Register. A bit value
one indicates an enabled condition. Consequently, a
bit value of zero indicates a disabled condition. The
Service Request Enable Register is cleared by send-
ing *SRE0. The generator always ignores the value
of bit 6. Summary of *SRE messages is given in
the following.
*SRE0 - No mask.
*SRE1 - Not used.
*SRE2 - Service request on offset error.
*SRE4 - Service request on pulse width error.
*SRE6 - Service request on ramp.
*SRE16 - Service request on MAV.
*SRE32 - Service request on ESB.
*SRE128 - Not used.
4-14-2. Standard Event Status Register (ESR)
The Standard Event Status Register is a special
application of the status reporting. IEEE-488.2 docu-
ment specifies the meaning of each bit of this
register. The 8 bits of the ESR have been defined
by the IEEE-488.2 as specific conditions which can
be monitored and reported back to the user upon
request.
The Standard Event Status Register is destruc-
tively read with the *ESR? common query. The
Standard Event Status Register is cleared by a *CLS
common command, on power-on, and when read by
*ESR?.
The arrangement of the various bits within the
register is firm and is required by all GPIB instruments
that implement the IEEE-488.2. Description of the
various bits is given in the following.
Bit 0 - Operation Complete. Generated in response
to the *OPC command. It indicates that the device
has completed all selected and pending operations
and is ready for a new command.
Bit 1 - Request Control. This bit operation is
disabled on model 8020.
Bit 2 - Query Error. This bit indicates that an
attempt is being made to read data from the output
queue when no output is either present or pending.
Bit 3 - Device Dependent Error. This bit is set
when an error in a device function occurs. For
example, the following <Program Message> will cause
DDE error: 0;0. Both parameters
are legal and within the specified limits, however,
the function generator is unable to generate such
an amplitude and offset combination. Following the
Device Dependent Error the generator continues to
process the input stream.
Bit 4 - Execution Error. This bit is generated if
the <Program Data> element following the header
is outside of the legal input range of the generator.
Bit 5 - Command Error. This bit indicates the
generator received a command that was a syntax
error, or a command that the device does not
implement. A GET receive inside a <Program Mes-
sage> will also cause a Command Error.
Bit 6 - User Request. This event bit indicates
that one of a set of local controls, the MANUAL
push-button in this case, has been activated. This
event bit occurs regardless of the remote or local
state of the device.
Bit 7 - Power On. This bit indicates that the
device’s power source was turned off, then on, since
the last time that the register was read.
4-14-2-1. Standard Event Status Enable
Register (ESE)
The Standard Event Status Enable Register allows
one or more events in the Standard Event Status
Register to be reflected in the ESB summary-message
bit. The Standard Event Status Enable Register is
an 8-bit register that enables corresponding summary
messages in the Standard Event Status Register.
Thus, the application programmer can select reasons
for the model 8020 to issue a ESB summary-message
bit by altering the contents of the ESE Register.
The Standard Event Status Enable Register is
read with the *ESE? common query. The response
to this query is an number that represents the sum
of the binary-weighted value of the Standard Event
Status Enable Register.
The Standard Event Status Enable Register is
written using the *ESE common command followed
by a <Decimal Numeric Program Data> element
representing the bit values of the Register. A bit
value one indicates an enabled condition. Conse-
quently, a bit value of zero indicates a disabled
condition. The Standard Event Status Enable Register
IEEE-488.2 Operation Model 8020
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