如何使用pic24fj256gb206上的rtc时钟？

我在几个项目中使用过这个PIC芯片，但它们都独立于日历时钟功能，所以我不想读它。现在，我需要在即将到来的项目中使用RTC，我有几个问题，因为我的搜索没有成功：1）电池连接，因为RTC需要在设备断电时运行，所以我想我必须以某种方式将电池连接到它。当PIC关机时电池在保持RTC运行吗？建议使用电池类型？2)RTCI的初始化可以使用软件片段在通电时初始化RTC，同时处理这两种情况（首先启动RTC，然后从已经运行的RTC开始）。我真的不知道这是怎么做到的，所以一个代码示例会很好。3)RTCIf的精度，我使用一个32768Hz的时钟晶体，然后我可以得到相当精确的定时。也就是说需要使用额外的电容器或可变电容器来拉动振荡器吗？欢迎任何建议。



      以下为原文

    I have used this PIC chip on several projects but they were all independent of calendar clock functions so I did not care to read up on it. Now I need to use the RTC in an upcoming project and I have a few questions since my searches were not successful:
1) Connection of a battery
Since the RTC needs to be running also when the device is powered down I assume I have to somehow connect a battery to it.
Are there any circuit examples for this where the battery is keeping the RTC running while the PIC is switched off?
Recommendations of battery type to use?

2) Initialization of the RTC
I could use software snippets for initializing the RTC on power up taking care of both cases (first start and start with the RTC already running. I do not really know how this can be done so a code example would be good.

3) Accuracy of RTC
If I use a 32768 Hz clock crystal could I then get decent accuracy of timing. I.e. is there a need to pull the osciallator using extra capacitors or a variable cap?

Any suggestions welcome.