2015/11/10
DSP控制器原理及应用
扩展存储器的最小系统需要的控制总线CB思考题2-7:输出变高阻
XRD(读控制信号,输出/高阻)在什么情况下发生?高阻有何用? Read Enable. Active-low read strobe. The read strobe waveform is specified, per zone basis, by the Lead, Active, and Trail periods in the XTIMINGx registers. NOTE: The XRD and XWE signals are mutually exclusive.
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DSP控制器原理及应用
扩展存储器的最小系统需要的控制总线CB XWE引脚(写控制信号,输出/高阻) Write Enable. Active-low write strobe. The write strobe waveform is specified, per zone basis, by the Lead, Active, and Trail periods in the XTIMINGx registers. 22