Remote Control Interfaces and Protocols
R&S
®
NRP Series
48
Getting Started 1419.0170.02 ─ 12
7.1
USB Interface
For remote control using USB connection, the computer and the power sensors
must be connected via the USB interface. A USB connection requires the VISA
library to be installed. VISA detects and configures the R&S power sensors auto-
matically when the USB connection is established. Apart from the USBTMC driver
(which comes with the installation of the R&S NRP Toolkit), you do not have to
install a separate driver.
USB Test & Measurement Class Specification (USBTMC) is a protocol that is built
on top of USB for communication with USB devices. It defines class code infor-
mation of the sensor, that identifies its functionality to load the respective device
driver. Using VISA library, it supports service request, triggers and other opera-
tions that are commonly found in GPIB devices.
Besides USBTMC, the NRP legacy protocol is available to ensure the compatibil-
ity of the R&S NRP power sensors with the R&S
NRP
‑
Z series of power sensors.
The usage of this protocol is not recommended for new applications.
The resource string represents an addressing scheme that is used to establish a
communication session with the sensor. It is based on the sensor address and
some instrument- and vendor-specific information.
USB Resource String
The syntax of the used USB resource string is:
USB::<vendor ID>::<product ID>::<serial number>[::INSTR]
where:
●
<vendor ID> is the vendor ID for Rohde & Schwarz (0x0AAD)
●
<product ID> is the product ID for the Rohde & Schwarz sensor
●
<serial number> is the individual serial number on the rear of the sensor
Table 7-2: R&S
NRPxxA(N) USB product IDs
R&S NRP power sensor
USB product ID
R&S
NRP6A
0x0178
R&S
NRP6AN
0x0179
R&S
NRP18A
0x014E
R&S
NRP18AN
0x014F
USB Interface
