In the MSP430F2272 errata there are 2 possible workaround alternatives described for the BCL12. In order to avoid the activation of BCL12:
1.) Only one intermediate step is done when switching RSEL from <12 to >13 or vice versa.
2.) RSEL is changed step by step (one by one).
Citation including 2.):
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.
Question: Do both alternatives safely prevent the activation of BCL12, especially prevent the complete DCO stop?
This means: does also alternative 1.) safely prevent it? (The fix with alternative 1.) seems not to provide a necessary condition for activating BCL12 according to Description of BCL12 in the errata sheet)
Related to 1.
For switching RSEL from <12 to >13, at “Workaround” it is described that the intermediate step should be RSEL = 7 (default value).
Just to be sure, which of the following both switching procedures 1.a.) or 1.b.) should be preferred, starting with value of RSEL < 12 ?
1.a.)
According to the described workaround:
- Set RSEL = 7
- Set RSEL = 14 or 15
1.b.)
According to the described condition for activating BCL12 at “Description” – BCL12 might be activated when switching RSEL from < 12 to > 13:
- Set RSEL = 13
- Set RSEL = 14 or 15
Best regards,
Frank