Hello,
I have a problem about suspend/resume of the USB interface.
The part number is AM3703.
The problem is that the PORTSC.Suspend (the bit7 of the PORTSC register) is not cleared,
when PortSC.FPR is set then cleared.
Thus, the communication did not resume.
The occurrence frequency is about 0.1%.
Do you have the same experience and any solutions?
I will work around the problem by setting OPP to 4 before "resume".
Is this method validity?
The conditions and the summaries are followed:
- The problem appear during the long-term test.
- The "suspend" and the "resume" are repeated per 1 minute as the long-term test.
- The mode is into PHYSI-Auto. (i.e. ULPI)
- The "suspend" is all clear, and "resume" has a problem.
- The workaround described in Errata (Advisory 1.44 and 1.79) did not solve.
thanks
Nomoto