Racal Instruments 3162A/B, User Manual

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User Manual 3162A/B
SCPI Command Reference 4-17
*STB? - Query the Status Byte summary register. The *STB?
command is similar to a serial poll but is processed like any other
instrument command. The *STB? command returns the same result as
a serial poll, but the "request service" bit (bit 6) is not cleared if a serial
poll has occurred.
*TRG - Triggers the generator from the remote interface. This command
effects the generator if it is first placed in the Trigger or Burst mode of
operation and the trigger source is set to "BUS".
*TST? - Implements an internal self-test and returns a value as
described below. Approximately 90% of the Model 3162B functionality
is tested.
0 - Selftest passed
1 - CPU to peripherals communication failure
2 - DAC control, output amplifier, amplitude & offset control
failure – Channel A
4 - DAC control, output amplifier, amplitude & offset control
failure – Channel B
8 - Waveform memory failure - Channel A
16 - Waveform memory failure - Channel A
32 - Clock divider failure
64 - Clock generator failure
128 - Trigger & internal trigger failure
256 - Sequence advance circuit failure
512 - PLL circuit failure
More than one failure can be reported at one time. For example, the
returned value 17” indicates both a DAC/Output Amplifier problem and
a sequence/burst generator problem exist.
* WAI – Wait for all pending operations to complete before executing any
additional commands over the interface.
The SCPI Status
Registers
The Model 3162B uses the Status Byte register group and the Standard Event
register group to record various instrument conditions. Figure 4-1 shows the
SCPI status system.
An Event Register is a read-only register that reports defined conditions within
the generator. Bits in an event register are latched. When an event bit is set,
subsequent state changes are ignored. Bits in an event register are
automatically cleared by a query of that register or by sending the *CLS
command. The *RST command or device clear does not clear bits in an event
register. Querying an event register returns a decimal value, which corresponds
to the binary-weighted sum of all bits, set in the register.
An Event Register defines which bits in the corresponding event register are
logically ORed together to form a single summary bit. The user can read from