USB Communication

[Edmi]

Hello,

I'm having some trouble with an usb communication that i'm trying to implement. First of all, I'm working with a development kit containing one LPC2368 (ARM based) focused on send and transfer data between it and the PC.

As a starter point, I downloaded an example source code (written in C) to the LPC, which configures it as a HID device and was able to communicate with the software called SimpleHIDWrite (the endpoints of the device are defined as interruption). After that the logical path was to install the Visa driver and try to send information of my own and everything was going great in my VI until the VISA Write or VISA Read block, because they point to an error (Unable to start operation because setup is invalid (due to attributes being set to an inconsistent state).

I first thought the problem was due the device being defined as HID, however Measurement & Automation was capable of receiving the Manufacturer, Device Information as well as the VID and PID, also VISA Open worked just fine. Therefore i came to the conclusion that the error source was on VISA Write, Read and the Interruption Handler Blocks.

So i would like to know if there's necessary configurations that i'm missing or if my line of thought is completely wrong, anyhow i hope you guys can help me.

Thank you in advance,

Edson Menegatti

[kzietlow]

It looks like you are missing a driver. Just because a USB device is reporting to be a HID device doesn't mean you can talk to it using VISA read or write operations (a USB mouse is a HID too...).

I'm sure that the NXP example will include a virtual COM driver that will bind to the VID / PID combination. Once that is installed you should be able to open it as a serial port and talk to the micro through VISA.

Klaus

[omprakash]

Based on your information provided,i assume that Baudrate->9600,parity bit and other basic info has been fed correctly.

I also faced similar problem and i agree with kzietlow.Install Driver required for USB communication of your ARMxxxx.It will work.

[Edmi]

Yeah, I understand your point, but I thought that the driver created by VISA Wizard was enough since Max recognized it and got all the necessary information.

So what you guys saying is that I need other driver? More specific to this ARM?

And to the point mentioned by kzietlow. Binding the VID and  PID to a COM port, won't make me lose the features that differs USB and common serial communication? 

Gladly,

Edson

[PabloT]

I am in the same situation. What can we do?