CYUSB306X datasheet(31/37 Pages) CYPRESS

31 / 37 page

CYUSB306X

Document Number: 001-87516 Rev. *L

Page 31 of 37

2. USB enumeration failure in USB boot mode when CX3 is self-powered.

■ Problem Definition

CX3 device may not enumerate in USB boot mode when it is self-powered. The bootloader is designed for bus power mode. It

does not make use of the VUSB pin on the USB connector to detect the USB connection and expect that USB bus is connected

to host if it is powered. If CX3 is not already connected to the USB host when it is powered, then it enters into low-power mode

and does not wake up when connected to USB host.

■ Parameters Affected

N/A

■ Trigger Conditions

This condition is triggered when CX3 is self-powered in USB boot mode.

■ Scope of Impact

Device does not enumerate

■ Workaround

Reset the device after connecting to USB host.

■ Fix Status

No fix. Workaround is required.

3. Extra ZLP is generated by the COMMIT action in the GPIF II state.

■ Problem Definition

When COMMIT action is used in a GPIF-II state without IN_DATA action then an extra Zero Length Packet (ZLP) is committed

along with the data packets.

■ Parameters Affected

N/A

■ Trigger Conditions

This condition is triggered when COMMIT action is used in a state without IN_DATA action.

■ Scope of Impact

Extra ZLP is generated.

■ Workaround

Use IN_DATA action along with COMMIT action in the same state.

■ Fix Status

No fix. Workaround is required.

CYUSB306X Datasheet(PDF) 31 Page - Cypress Semiconductor