Tektronix TDS644B Caulking Gun User Manual


 
TDS Family Oscilloscope Programmer Manual
3–1
Status and Events
The digitizing oscilloscope provides a status and event reporting system for the
GPIB interface. This system informs you of certain significant events that occur
within the digitizing oscilloscope.
The digitizing oscilloscope status handling system consists of five 8-bit registers
and two queues. This section describes these registers and components. It also
explains how the event handling system operates.
Registers
The registers in the event handling system fall into two functional groups:
H Status Registers contain information about the status of the digitizing
oscilloscope. They include the Standard Event Status Register (SESR) and
the Status Byte Register (SBR).
H Enable Registers determine whether selected types of events are reported to
the Status Registers and the Event Queue. They include the Device Event
Status Enable Register (DESER), the Event Status Enable Register (ESER),
and the Service Request Enable Register (SRER).
The Standard Event Status Register (SESR) and the Status Byte Register (SBR)
record certain types of events that may occur while the digitizing oscilloscope is
in use. IEEE Std 488.2–1987 defines these registers.
Each bit in a Status Register records a particular type of event, such as an
execution error or service request. When an event of a given type occurs, the
digitizing oscilloscope sets the bit that represents that type of event to a value of
one. (You can disable bits so that they ignore events and remain at zero. See the
Enable Registers section on page 3–3.) Reading the status registers tells you
what types of events have occurred.
The Standard Event Status Register (SESR). The SESR, shown in Figure 3–1,
records eight types of events that can occur within the digitizing oscilloscope.
Use the *ESR? query to read the SESR register. Reading the register clears the
bits of the register so that the register can accumulate information about new
events.
Status Registers