本帖最后由 fq1110 于 2012-12-10 09:37 编辑
我在使用NXP PCF8563 RTC时，读取寄存器时，PCF8563总是提示
rtc-pcf8563 1-0051: low voltage detected, date/time is not reliable.
raw data is st1=08, st2=c0, sec=d5, min=a6, hr=c0, mday=c0, wday=d0, mon=40, year=00
rtc-pcf8563 1-0051: retrieved date/time is not valid.
sec寄存器第7位总是1,以下是RTC部分原理图
我这里VDD是直接接的电池，CLKOUT,INT悬空，
有人遇到过这问题吗？
PCF8563 datasheet上有这么一句：
The PCF8563 has an on-chip voltage-low detector (see Figure 7). When VDD drops below
Vlow, bit VL in the VL_seconds register is set to indicate that the integrity of the clock
information is no longer guaranteed. The VL flag can only be cleared by using the
interface.
但是我用示波器测了，VDD一直处于3V，没有发生变化。
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