ICS ELECTRONICS 9099, Инструкция по эксплуатации

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3.8.13 Locking Setup Parameters
Some of the 9099’s configuration parameters can be locked to prevent ac-
cidental change by the end user. These lockable parameters are noted by a #
symbol in Tables 1-3. Locked parameters cannot be queried or changed while
locked. Any command that addresses a locked parameter is not executed, the
Command Error bit in the Event Status Register is asserted and the ERR LED
is lit. The lock function is saved by the *SAV 0 command.
An example is:
CAL:LOCK ON ‘blocks unauthorized changes
*SAV 0 ‘saves lock condition
CAL:LOCK OFF ‘unlocks setup parameters
While lock is enabled, the end-user can only change and save any non-locked
parameter.
3.8.14 Generating Service Requests (SRQs) from Modbus Errors
Figure 3-1 shows the 9099's Status Reporting Structure. All Modbus Error codes
are placed in the Modbus Error Register at the top of the figure. If the proper
Event Status and Status Byte register bits are enabled, any Modbus Error code
will generate a Service Request. The commands to enable the bits are:
*ESE 64 ‘enables ESR bit 6
*SRE 32 ‘enables Status Byte bit 5
Some Modbus Errors set specific bits in the Questionable Event Register. To
generate a Service Request from a specific event, its bit must be enabled. The
following commands enable Service Requests for Timeouts and CRC errors
only:
STAT:QUES:PTR #h3000 ‘enables positive going bits 12
and 13 to set bits in the
Questionable Event Register
STAT:QUES:ENAB #h3000 ‘enables Event bits 12 and 13
*SRE 8 ‘enables Status Byte bit 3
In both cases, the user needs to reset the event cause and clear the Service
Request so another error will cause another Service Request. In case one, this
is done by reading the Modbus Error Register with the E? query. In case two,
the Questionable Event Register must be read to clear the set event bits.