1 Reply Latest reply on Sep 10, 2017 8:38 PM by Madhu Lakshmipathy

    USB1.1 packetsize issue

    qiang.fan_2104626

      Hi,

           I continued to discuss the issue about USB1.1,last time  maybe I gave inadequary message about this issue.

           Firstly,I introduce my using scene, I choose the fx3 firmware,which is wanted to use the usb peripheral mode,the usb worked in full speed mode.

      According to the USB2.0 or USB1.1 protocol,In full speed mode ,the packesize can be set 8,16,32,64bytes,we can set wMaxPacketSize in the device descriptor.

           Now I met the issue ,I set wMaxPacketSize is 8bytes,the usb can't be found,only set wMaxPacketSize is 64bytes,the usb can run.

      I want to know if the wMaxPacketSize can be set 8bytes in full speed,and the relationship betweenthe bcdUSB and wMaxPacketSize in the device descriptor

           Please give me some support or example,guys.

       

      Thanks