ICS ELECTRONICS 9099, Инструкция по эксплуатации

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3-13
3
The recommendation is to follow each query by reading the result. Testing
the 9099's Output Queue's summary bit before addressing the device to talk is
not necessary or desirable.
3.3.7 Status byte Register
The 9099 generates a Service Request (SRQ) whenever any of the enabled bits
in the Status Byte Register become true. The Status Byte Register may be read
with the device_readstb function or with the *STB? query. The device_readstb
function resets the RQS bit; the *STB? query does not change the bit. The
Status Byte Register is enabled by setting the corresponding bits in the Service
Request Enable Register with the *SRE command. e.g.
*SRE 160 ‘Sets the SRE Register to 1010 0000 which
enables just the Event Status and Questionable
summary bits to generate SRQs.
3.3.8 Saving the Enable and Transition Register Values
When the PSC flag is set, the SRE, ESE and SCPI Enable and Transition Reg-
isters are cleared at power turn-on. When the PSC flag is cleared, the SRE,
ESE, and SCPI Conditional and Operational Enable and Transition Register
values are restored at power turn-on time to their values prior to the power
turn-off. The PSC flag is defaulted to on. Use the *PSC 0 command to dis-
able the PSC flag and restore the current register values at power turn-on as
shown in the example. e.g.
STAT:OPER:ENAB 1 'enables Status A bit
STAT:OPER:NTR 1 'enables negative transition
*PSC 0; ESE 96; SRE 32 'saves the PSC flag as off plus
the ESE and SRE values
and the Operational Enable and
Transition
register values.
CAUTION: When the PSC flag is cleared, any change made to the SRE, ESE
or SCPI Enable and Transition Registers are saved in nonvolatile memory.
Excessive use of this save function can wear out the flash memory and shorten
the unit's life.
3.3.9 488.2 Differences from 488.1 Devices
The IEEE 488.1 Device Clear command does not reset any device outputs
as would be expected of a 488.1 device. To reset the device outputs, use the
*RST (Reset) or *RCL 0 command.