PXS20RM Datasheet, PDF (1301/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Sine Wave Generator (SWG)
44.5.2 Preserving the SWG_CTRL data
After you make a change to the SWG_CTRL register, the SWG expects that you will preserve this data for
at least 50 clock cycles. Failure to do so may cause unexpected output from the SWG.
Freescale Semiconductor
PXS20 Microcontroller Reference Manual, Rev. 1
44-5