Specifications

Status and Events
3-2
TDS3000, TDS3000B, and TDS3000C Series Programmer Manual
Table 3- 1: SESR bit f unctions
Bit Function
7 (MSB) PON (Power On). Shows that the oscilloscope was powered on.
6 URQ (User Request). Not used.
5 CME (Command Error). Shows that an error occurred while the oscilloscope
was parsing a command or query. Command error m essages are listed in Table
3--4 on page 3--12.
4 EXE (Execution Error). Shows that an error occurred while the oscilloscope was
executing a command or query. Execution error messages are listed in Table
3--5 on page 3--14.
3 DDE (Device Error). Shows that a device error occurred. Device error
messages are listed in Table 3--6 on page 3--17.
2 QYE (Query Error). Shows that either an attempt was made to read the Output
Queue when no data was present or pending, or that data in the Output Queue
was lost.
1 RQC (Request C ontrol). Not used.
0 (LSB) OPC (Operation Complete). Shows that the operation is complete. This bit is
set when all pending operations complete following an
*OPC command.
The Status Byte Register (SBR) — shown in Figure 3--2, records whether output
is available in the Output Queue, whether the oscilloscope requests service, and
whether the SESR has recorded any events.
Use a Serial Poll (GPIB only) or the *STB? query to read the contents of the
SBR. The bits in the SBR are set and cleared depending on the contents of the
SESR, the Event Status Enable Register (ESER), and the Output Queue. When
you use a Serial Poll to obtain the SBR, bit 6 is the RQS bit. When you use the
*STB? query to obtain the SBR, bit 6 is the MSS bit. Reading the SBR does not
clear the bits.
—
RQS
ESBMAV————
MSS
7
6
543210
6
Figure 3- 2: The Status Byte Register (SBR)