usblib pipe Error

[sabin]

I am  using  Fx3 device connected to the pc send and recive control with  XferData function and it is working ok.

on an  ubunto with libusb using libusb_control_transfer()  function I get (-9 )PIPE ERROR or read 

send data:

ret_val = libusb_control_transfer(handle, LIBUSB_REQUEST_TYPE_CLASS & 0x7F, 0x27, 1, 0, (unsigned char *)data, m_len, 500);

receive data:

 ret_val = libusb_control_transfer(handle, LIBUSB_REQUEST_TYPE_CLASS | 0x80, 0x28, 1, 0, (unsigned char *)data, m_len, 500);

can some one help solving the pipe error on receive data

thanks

Sabin

[Rashi_Vatsa · Accepted solution]

Hello,

LIBUSB_ERROR_PIPE is seen when the control request was not supported by the device, so first, please check if the control request is handled properly in FX3.

Please share the USB traces using a USB analyzer (like Wireshark) to understand the status of the USB control transfer. Also, if possible, please share the firmware you are using.

To narrow down the issue, please let me know if the error is seen with cyusb_linux host application (in FX3 SDK for Linux)