PIC24FJ256GB406 DAC输出问题

嗨，我正在利用PIC24FJ256GB406的DAC来转换我从加速度计接收的数据，并且我用示波器看到输出的信号。问题是，只有在高于确定电压的情况下，数据才正确地显示在示波器上。我的意思是，如果我做一个for循环，在DAC1DATA寄存器中写入0到1023的所有数字，我只能在示波器上看到一半的类锯齿信号。我想在示波器上发布一个信号的图像，让我写的东西更容易应付，但是论坛给了我一个错误（你没有权限访问我每次上传图像的时候。有人能帮我吗？我对我的英语感到抱歉，如果我漏掉了一些重要的东西（这是我的第一个DAC项目），所以请友好地告诉我，如果你需要一些其他的信息。谢谢。



      以下为原文

    Hi,
I am utilizing the DAC of the PIC24FJ256GB406 to convert the data that I receive from an accelerometer and I am using an oscilloscope to see the outputted signal. The problem is that the data are correctly showed on the oscilloscope only if higher than a determined voltage.
What I mean is that if I make a for-loop where I write in the DAC1DAT register all the digits from 0 to 1023, I see on the oscilloscope only half of the saw-like signal. I wanted to post an image of the signal from the oscilloscope to make what I wrote more comprhensible but the forum gives me an error (You don't have permission to access  everytime I try to upload an image.

Can someone help me about it?
I am sorry for my english and if I have left out something important (it's my first DAC project), so please be kind and tell me if you need some other information.

Thank you
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