Rohde & Schwarz NRP TWG Series, Руководство пользователя

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Remote Control Basics
R&S
®
NRPxxTWG
111 User Manual 1178.8371.02 ─ 04
Table 9-4: Meaning of bits used in the status byte
Bit No. Meaning
0 Not used
1 Device status register summary bit
Depending on the configuration of the sensors status register, this bit is set when a sensor
is connected or disconnected or when an error has occurred in a sensor.
See Chapter 9.3.5, "Device Status Register" , on page 112.
2 Error queue not empty
The bit is set if the error queue has an entry. If this bit is enabled by the service request
enable register, each entry of the error queue generates a service request. An error can
thus be recognized and specified in detail by querying the error queue. The query yields a
conclusive error message. This procedure is recommended since it considerably reduces
the problems of IEC/IEEE-bus control.
3 Questionable status register summary bit
This bit is set if an
EVENt
bit is set in the
QUEStionable
status register and the associ-
ated
ENABLe
bit is set to 1. A set bit denotes a questionable device status which can be
specified in greater detail by querying the Questionable status register.
See Chapter 9.3.6, "Questionable Status Register" , on page 113.
4 MAV bit (Message available)
This bit is set if a readable message is in the output queue. This bit can be used to auto-
mate reading of data from the sensor into the controller.
5 ESB: Standard event status register summary bit
This bit is set if one of the bits in the standard event status register is set and enabled in the
event status enable register. Setting this bit denotes a serious error which can be specified
in greater detail by querying the standard event status register.
See Chapter 9.3.7, "Standard Event Status and Enable Register (ESR, ESE)" ,
on page 115.
6 MSS: Master status summary bit
This bit is set if the sensor triggers a service request. This happens if one of the other bits
of this register is set together with its enable bit in the service request enable register
(SRE).
7 Operation status register summary bit
This bit is set if an
EVENt
bit is set in the operation status register and the associated
ENABLe
bit is set to 1. A set bit denotes that an action is being performed by the sensor.
Information on the type of action can be obtained by querying the operation status register.
See Chapter 9.3.8, "Operation Status Register" , on page 116.
9.3.4 IST Flag and Parallel Poll Enable Register (PPE)
Similar to the service request (SRQ), the IST flag combines the complete status infor-
mation in a single bit. It can be queried by a parallel poll or by
*IST?
.
The parallel poll enable register (PPE) determines which bits of the STB affect the IST
flag. The bits of the STB are ANDed with the corresponding bits of the PPE; bit 6 is
also used, in contrast to the service request enable register. The IST flag is obtained
by
ORing
all results together.
Status Reporting System