I get frequently asked questions about how to remote control the R&S CMU200 and CRTU. Some want to program their own application, some just have issues getting my software to run.
So here are a few hints, tips and tricks!
SCPI - What is it?
GPIB - What is it?Wikipedia explains:
"IEEE 488 is a short-range digital communications 8-bit parallel multi-master interface bus specification. IEEE 488 was created as HP-IB (Hewlett-Packard Interface Bus) and is commonly called GPIB (General Purpose Interface Bus). It has been the subject of several standards."
VISA - What is it?
"Virtual instrument software architecture, commonly known as VISA, is a widely used I/O API in the test and measurement (T&M) industry for communicating with instruments from a computer. VISA is an industry standard implemented by several T&M companies, such as, Anritsu, Bustec, Keysight Technologies, Kikusui, National Instruments, Rohde & Schwarz, and Tektronix."
Keysight Connection Expert 2018
It is one of many VISA implementations.
Connecting through RS-232
- You need to select the serial communication protocol and choise are NONE, XON/XOFF or CTS/RTS. If you are using a full featured null modem cable, then you can select the CTS/RTS mode, which uses handshaking through dedicated lines. If you are using just a simple cable (2-3, 3-2 and 7-7), you can try XON/XOFF or NONE.
- The best way to connect the device to the PC is to use a regular COM-port on your motherboard. This will fully support the RS-232 communication. The problem is that modern computers normally don't have this port anymore!
The work-around consists in using a USB to RS.232 adapter. These can be purchased cheaply, but beware: not all work correctly!
Problems can be expected with adapters using the Prolific chip, as this is normally a fake chip and the official driver will not work! You need to use an old Prolific driver (pre 2010), but those won't implement XON/XOFF or CTS/RTS handshake properly, so you need to use NONE. Even so, some users experience problems with Time Out on the VISA protocol. This is not a problem of my software!
I had good results with adapters based on the CH340 chip. These can be bought for the ridiculous price of 1€ (including free shipping):
- Serial Communication is about 10 times slower than using a GPIB adapter! This means that the spectrum refresh rate will be slow. It works, but it is no real fun.
Connecting through a GPIB interface
Configuring the connection
For RS-232 Connection: