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. j2 K; a$ S' G2 P' ?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! e0 E7 E+ I* s
" c! C' k5 K Y$ B# R( j8 D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!3 B7 {$ g8 i- w/ _' P
. F+ l; q' U; P; d# z* sLong Start-Up Time& e! D7 y. d4 H! k% g9 O* w, R
A 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./ A; {! w* X. }7 X. F" i" e) W* s
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