4. History Data Details
•
Checking the VBUS supply control circuit and the interface peripheral circuits
1. Connect a USB device (not USB hub) to the LSI and confirm that “USB: VBUS
overcurrent” does not appear in the history.
* Otherwise, there may be a problem in the VBUS supply control circuit.
2. Confirm that “USB: LS device”, “USB: FS device”, or “USB: HS device” in the
history match the speed mode of the USB device connected.
* If not, there may be a problem in the interface peripheral circuit or with signal
quality.
3. Confirm that the history entry appears as shown below according to the type of
USB device connected.
•
Confirm that “USB: storage device” appears in the history if the USB device
connected is a storage device.
•
Confirm that “USB: unsupported device” appears in the history if the USB
device connected is an unsupported device.
* If not, there may be a problem with signal quality.
•
Checking USB hub operation
1. Connect a USB hub to the LSI. Confirm that “USB: VBUS overcurrent” does not
appear in the history.
* Otherwise, there may be a problem in the VBUS supply control circuit.
2. Confirm that “USB: FS device” or “USB: HS device” appears in the history and
matches the speed mode of the USB hub connected.
* If not, there may be a problem with signal quality.
3. Connect a USB device to the USB hub connected, and check that the history entry
appears as shown below, depending on the type of USB device connected.
•
Confirm that the “USB: storage device” appears in the history if the USB
device connected is a storage device.
•
Confirm that “USB: unsupported device” appears in the history if the USB
device connected is an unsupported device.
* If not, there may be a problem with signal quality.
14
EPSON
S1R72U16 Development Support
Manual (Rev.2.00)
