Users Guide: DS80C390 Supplement Manual

High-Speed Microcontroller User’s Guide: DS80C390 Supplement
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ADDENDUM TO SECTION 7: POWER MANAGEMENT
The DS80C390 supports the general power management features of the DS87C520 described in the High-
Speed Microcontroller User’s Guide. Exceptions are noted below.
POWER MANAGEMENT MODES
Power management mode 1 (PMM1) is not supported on the DS80C390.
SWITCHING BETWEEN CLOCK SOURCES
The ring oscillator on the DS80C390 is similar to that on the DS80C320. As such it does not support the
“run from ring” feature which allows the microprocessor to use the ring oscillator as a clock source after
the external crystal has stabilized (CKRY = 1).