PIC24fj64gb002：TRIS位未设置为输入

我试图解决一个马克西姆1线电路，并在初始存在检测序列，我必须切换我的TrISB5引脚14到一个输入，从一个输出。电路不工作，所以我用tiSISB寄存器上的表进行调试。我把我的输入行移到主函数中：行：TySISB5＝1；在运行该线之后，手表指示TrISB5保持零，如在输出中。我不明白为什么它没有设置为输入逻辑1。有什么想法吗？非常感谢你的帮助。



      以下为原文

    I'm trying to trouble shoot a Maxim 1 - wire circuit and during the initial presence detect sequence, I have to switch my TRISB5 pin 14 to an input, from an output. The circuit isn't working so I ran it on Debug with a Watch on the TRISB register. I moved my set for input line into the main function with the line: _TRISB5 = 1;. After running past that line, the watch indicates that the TRISB5 stays a zero, as in output. I do not understand why it isn't setting to an input logic 1. Any ideas ? And thank you so much for help in advance.
int main(void)
{
    // initialize the device
    SYSTEM_Initialize();
    _TRISB5 = 1;// Here's the line. It's not setting in debug mode.
    lcd_init();
    reset_detect();
    while(1)
    ClrWdt();
   
}