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; k; A& p+ l, Y( R) T% D不確定是不是這個問題造成的,但可以參考一下這些資料。 O5 {* P1 Y+ t; g8 e0 ~
& E4 p: R& N: Y1 P0 `" N7 [1 l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!
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3 R# L: g3 `' | m; zLong Start-Up Time
5 R6 u0 o# p, A4 KA 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.
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