AnsweredAssumed Answered

CF51JM not reliable at full PLL speed

Question asked by Robert Bailey on Oct 26, 2011
Latest reply on Jan 18, 2012 by TomE

I am working on some prototypes of a new product,  and am getting wierd lockups and fail-to-start issues when the PLL is set to 48mhz (for a bus speed of 24).  This clock speed is required for USB to work,  so its important to determine the issue.


I have tried 8 mhz and 12 mhz crystals,  and the problem is essentially unchanged.  Sometimes the CPU locks up very soon after powerup,  sometimes it will run for a while.


I am using CW6.3 with ProcessorExpert.


If I reduce the clock,  the symptom goes away (not sure if its truly solved,  as testing is preliminary), but this product needs USB to be functional.


Is there some errata on this?  Does it sound familiar to anyone?