Are the IVI function available for TCP/IP and how is defined SCPI commands?

[toto 748]

I have several questions:
- Can I develop a driver for TCP/IP with the wizard "Create IVI instrument driver" if I use only Ivi functions ?

- How is the form of the command "writeBuffer" in the function Ivi_WriteInstrData(ViSession vi, ViConstString writeBuffer) ? Is there a specific protocol? What is SCPI ? Do I need to use SCPI ? Where can I find informations about that. ?


I don't have the instrument I want to drive but I need these informations to know if a project is possible. I bought LabWindows/CVI V6.0 especially to develop a such driver. I hope it will be possible. Thanks

[DiegoF]

Hi,

- Can I develop a driver for TCP/IP with the wizard "Create IVI instrument driver" if I use only Ivi functions ?

IVI is specified the way to organize the instrument data (using attributes and callbacks) and the IVI classes provide abstracted device models. The actual instrument I/O is not specified by IVI and you can use whatever you want.

Tipically, IVI drivers use VISA to perform instrument I/O. VISA is an standard API for instrument communication. VISA abstracts the bus used to communicate with the instrument. If you write your driver using VISA you can communicate with GPIB, Serial, TCP/IP (both raw socket and VXI-11). Usually a litle bus specific code is needed at initialization.

- How is the form of the command "writeBuffer" in the function
Ivi_WriteInstrData(ViSession vi, ViConstString writeBuffer) ? Is there a specific protocol?

ViConstString writeBuffer is just a string. The format of the string is instrument-dependent. Check the device user manual


- What is SCPI ? Do I need to use SCPI ? Where can I find informations about that. ?

SCPI is a standard on how the instrument organize the commands. Refer to the following articles:

Where Can I Find Documentation about the SCPI Specification?

GPIB Hardware and Software Specifications

DiegoF
National Instruments