How to configure a custom USB to GPIB device to be recognized by NI-MAX

[btyilmaz]

Hi everyone,

I was planning to use a custom USB to GPIB device. Is it possible to configure the device in a way that NI-MAX sees it as a GPIB device?  

[santo_13]

You created your own USB to GPIB device?

[btyilmaz]

Yes, a microcontroller is present on the board. It is connected to PC via USB and either VCP or FTDI's drivers can be used to communicate with it. What I want to know actually is that how can I see the GPIB devices connected to my converter in NI-MAX.

I am not experienced with VISA drivers but I used NI-VISA driver wizard to generate a PCI driver before. Is it possible to generate a driver for my USB controller and use only VISA drivers to see the GPIB instruments on the GPIB bus?

[santo_13]

so, if the microcontroller is connected to USB as VCP or FTDI, then it will automatically show up as a COM port.

NI MAX as the name suggests, is intended for NI manufactured devices and may not support all types of non-NI devices.

[Iwa6]

The GPIB-USB interface of Prlogix makes GPIB recognized by virtual COM from the computer through the chip of FTDI like the interface you made.
This is recognized as a serial device by NI-VISA.
Unlike genuine NI GPIB-USB interface, VISA cannot automatically recognize the connected GPIB device.
It is possible to force Prologix to be controlled serially from VISA, but the interface itself must also be controlled by commands.

Note

Prologix GPIB-USB Device Not Showing up in NI-MAX

LabView sample

[btyilmaz]

Thanks for the information. I saw that the ADLINK's USB-GPIB interface is fully compatible with NI-VISA. I am not sure how does that work. In the  page 13 of document ADLINK USB-3488A  it says that "ADLINK GPIB products are full compatible with NI-VISA." 

If anyone knows how that driver operates I would appreciate the help. 

[santo_13]

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@btyilmaz wrote:

Thanks for the information. I saw that the ADLINK's USB-GPIB interface is fully compatible with NI-VISA. I am not sure how does that work. In the  page 13 of document ADLINK USB-3488A  it says that "ADLINK GPIB products are full compatible with NI-VISA." 

If anyone knows how that driver operates I would appreciate the help. 

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Yeah, any COM port is VISA compatible, in the sense it will be detected and listed as a COM port. Same goes with any other USB-UART devices like FTDI, CP210x, CH34x etc., but it is not a GPIB port.

You can use the GPIB functions only with GPIB cards and this is possible only with NI GPIB cards I believe.

For everything else, it is VISA.

[Iwa6 · Accepted solution]

The USB-3488A uses a homegrown driver that mimics NI's GPIB driver, NI-488.2, to partially trick NI-VISA into being usable.
There are some VISA-enabled products that use compatible drivers like this, but they probably don't use the FTDI chip internally.

[btyilmaz]

Thank you for the clarification. I think I can try to trick NI-VISA too.

[Minions]

I was able to gather most of the information for using the FTDI chip within the Prologix controller here.  This is for their USB to GPIB controller.