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LPC4350 USB missing ACK in Bulk transfer while use device on Intel onboard USB 2.0 Controller (Intel 7 Series/C216 Chipset).

Question asked by Sebastian Vinezenz on Jun 23, 2017
Latest reply on Jun 27, 2017 by Sebastian Vinezenz

I'm using the ROM-API for LPC4350 to transfer huge amount of data from device to host (IN endpoint) while using USB bulk mode.

The problem is many missing ACK from host to device which leads to many retransmissions because of device is resending packet without DATA0/1 toggle. Viewing the USB transmission using the Beagle USB analyzer the ACKs are transmitted in a correct way.

This missing ACKs will only happen if using the device connected to host onboard chipset usb 2.0 controller which do have onboard USB hub.

Using the device connected to separate PCIe USB 3.0 contoller from ASUS or using the onboard Intel USB 3.0 controller there are no missing ACKs.


Is there a further problem concerning the errata sheet 3.16 USB.1 "USB0 unable to communicate with low-speed USB
peripheral in host mode when using full-speed hub"?