Hi guys,
I just noticed that the errata files for the value line were updated on 17th January. The new files contain a revision to the BCL12 text, adding the following advice:
"In the majority of cases switching directly to intermediate RSEL steps as described above will prevent the occurrence of BCL12. However, a more reliable method can be implemented by changing the RSEL bits step by step in order to guarantee safe function without any dead time of the DCO."
Might be of interest if you've been getting DCO lockups as I have recently!