In the screen capture shown here, the actual startup of an MSP430 digitally controlled oscillator (DCO) is plotted. It can be seen that from an interrupt event, the DCO is active and stable in well under 1µs – the F2131 DCO startup time is actually 204ns in this example. With the MSP430, clock start up is “instant-on” using the DCO with no delay or 2-speed clock startups. The associated application has instant access to the high-speed DCO from any operating mode.