Rohde & Schwarz SMC100A, Руководство по эксплуатации

Страница: 215 / 363

Remote Control Basics
R&S
®
SMC100A
198 Operating Manual 1411.4060.32 ─ 04
This part can be written into and read as required. Its contents are not affected by
reading.
●
NTRansition
The
Negative-TRansition
part also acts as a transition filter. When a bit of the
CONDition
part is changed from 1 to 0, the associated
NTR
bit decides whether the
EVENt
bit is set to 1.
– NTR bit =1: the
EVENt
bit is set.
– NTR bit =0: the
EVENt
bit is not set.
This part can be written into and read as required. Its contents are not affected by
reading.
●
EVENt
The
EVENt
part indicates whether an event has occurred since the last reading, it is
the "memory" of the condition part. It only indicates events passed on by the transition
filters. It is permanently updated by the instrument. This part can only be read by the
user. Reading the register clears it. This part is often equated with the entire register.
●
ENABle
The
ENABle
part determines whether the associated
EVENt
bit contributes to the
sum bit (see below). Each bit of the
EVENt
part is "ANDed" with the associated
ENABle
bit (symbol '&'). The results of all logical operations of this part are passed
on to the sum bit via an "OR" function (symbol '+').
ENABle
bit = 0: the associated
EVENt
bit does not contribute to the sum bit
ENABle
bit = 1: if the associated
EVENt
bit is "1", the sum bit is set to "1" as well.
This part can be written into and read by the user as required. Its contents are not
affected by reading.
Sum bit
The sum bit is obtained from the
EVENt
and
ENABle
part for each register. The result is
then entered into a bit of the
CONDition
part of the higher-order register.
The instrument automatically generates the sum bit for each register. Thus an event can
lead to a service request throughout all levels of the hierarchy.
6.5.3 Contents of the Status Registers
In the following sections, the contents of the status registers are described in more detail.
6.5.3.1 Status Byte (STB) and Service Request Enable Register (SRE)
The
STatus Byte
(STB) is already defined in IEEE 488.2. It provides a rough overview
of the instrument status by collecting the pieces of information of the lower registers. A
special feature is that bit 6 acts as the sum bit of the remaining bits of the status byte.
The STB is read using the command
​
*STB
​
or a serial poll.
The
STatus Byte
(STB) is linked to the
Service Request Enable
(SRE) register.
Each bit of the STB is assigned a bit in the SRE. Bit 6 of the SRE is ignored. If a bit is set
in the SRE and the associated bit in the STB changes from 0 to 1, a service request
Status Reporting System