I have tried using 'Visa write' icon from labview to send a byte data but it seems of having no response. I am not really sure what data need to be sent from the labview. LED1 & LED2 are used as USB event indicators. When UPDATE_LED is active, this command will be executed: Word _word //For word access(USBGEN_EP_SIZE msut be even) The C code for the data packet is like shown below: What do I have to fill in as the index, value, request type, and request for the 'Visa USB Control Out' ? Can someone help me? Thank youĪfter I looked through the C code, i figure out that I need to send an information in the form of 'data packet'. I assume that the output will be controlled by the 'Visa USB Control Out' (correct me if I am wrong), however it needs a set of input that I do not really understand. The attribute setting that i got from the 'Measurement and Automation' is:įor my first experiment, I just want to turn on and off the LEDs using a command from the Labview.

When I open the 'Measurement and Automation', I could find my device in the list. I have created a driver using NI-Visa and I have followed the procedure according to the tutorial from the NI website. I got the USB framework (MCHPFSUSB) from the Microchip website () and I used it to program the chip. I am using Labview 8.2 for the client software also NI-Visa 4.3.0 for the driver wizard. I am trying to make a simple input and output device using USB interface. The device consists of 4 LEDs which will be the indicator for the output. I have designed a hardware with PIC18F4550 microcontroller which supports USB module.

Pic usb 3 card