Fluke NORMA 4000 Operators, User Manual, Page: 27 / 184

Status Reporting System
Introduction
2
2-3
Introduction
The status reporting system stores all information on the current operating state of the
instrument, for example on any errors that have occurred. This information is stored in
status registers and in an error queue. The status registers and the error queue can be
queried via the IEC/IEEE bus. The information is of a hierarchical structure. The highest
level is formed by the status byte (STB) register defined in IEEE 488.2 and the associated
service request enable (SRE) mask register. The STB register receives information from
the standard event status register (ESR).It is also defined in IEEE 488.2 with the
associated standard event status enable (ESE) mask register and from the registers
STATus:OPERation and STATus:QUEStionable. These are defined by SCPI and contain
detailed information on the instrument.
The output buffer contains the messages the instrument returns to the controller. The
output buffer is not part of the status reporting system but determines the value of the
MAV bit in the STB register.
Structure of an SCPI Status Register
Each SCPI register consists of five parts each of 16 bits width that have different
functions (see Figure 2-1). The individual bits are independent of each other. Each
hardware status is assigned a bit number that is valid for all five parts. For example, bit 3
of the STATus:OPERation register is assigned to the hardware status “Wait for trigger”
for all five parts. Bit 15 (the most significant bit) is set to zero for all five parts. This
allows the controller to process the contents of the register parts as a positive integer.
15 14 13 12 3 2 1 0 CONDition part
15 14 13 12 3 2 1 0
& & & & & & & & & & & & &
EVENt part
15 14 13 12 3 2 1 0 ENABle part
To higher-order register
Sum bit
+
15 14 13 12 3 2 1 0
15 14 13 12 3 2 1 0 PTRansition part
NTRansition part
eya003.eps
Figure 2-1. Status Register Model