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不確定是不是這個問題造成的,但可以參考一下這些資料。. O( o5 z/ v8 p" e P9 J( Y
' z$ T) L5 u3 W1 |下面這段話是肥死卡好(Freescale)的技術文檔節錄下來的,講得一針見血、但內容較雜( 不只討論這個問題),我給你另一篇 ATMEL 的技術文檔,它專門討論 MCU 的 Start-up Time,淺顯易懂、還有一些電路上的建議!8 ?1 }0 J/ ^0 i% D6 {* r
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Long Start-Up Time
0 v8 w" U) i6 h0 M& C% aA long start-up time is usually a more common problem with low-frequency crystals, since they tend to start much more slowly than high-frequency crystals. One of the causes of a long start-up time is weak loop gain. Oscillator start-up times will also be affected by the rise time of the power supply. When the power supply has a sharp rise time, the crystal will experience an energy impulse that will usually make it start faster than it would using a power supply with a slow rise time.5 A8 ?( }# T8 p" X9 d
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