关于DsPIC33ep中Timer1的问题

大家好，因为我不能在任何真正的平台上测试我的代码，我所拥有的只是你的经验和数据表，所以让我提前感谢你的耐心和愿意分享，这意味着很多：回到我的问题，我想能够设置一个16位模式的计时器（时间）在此情况下R1），并在运行时更改溢出时间。我将溢出周期固定在0xFFFF上，并希望用TMR1寄存器来处理溢出时间。首先，这是改变TMR1寄存器或关闭和打开TMR1外围冗余的有效方式吗？其次，我想用PR1寄存器代替TMR1寄存器来改变溢出时间。当计时器溢出时，我必须清除TMR1中的值，所以它不一直计数，直到0xFFFF值再计数到PR1寄存器中的值为止吗？最后，在应用注意事项（DS70362，第10页）中有一段话：当出现以下任何一种情况时，预分频器计数器被清除：一个写入定时器寄存器（TMRX）或定时器控制（TXCON）寄存器：清除定时器控制中的定时器使能（Ton）位（TXCON & LT；15和GT）。任何设备ReSeSO都意味着，每当我更新TMR1寄存器或关机和外设时，我必须向TTKPS＆LT 1:0GT：（定时器输入时钟预选择位）写入寄存器。



      以下为原文

    Hello people , since I am not able to test my code on any real platform , all I have is your experience and the datasheets ,so let me  thank you in advance  for your patience and willingness to share , it means a lot :) Going back to my question , I want to be able to set a timer in 16 bit mode (Timer1 in this case) , and change the overflow time during the runtime . I fixed the overflow period at 0xFFFF and want to manipulate the overflow time with the TMR1 register .  Firstly is this a valid way of changing TMR1 register or is closing & opening of the the TMR1 peripheral redundant ?
void set_timer1(uint16_t period)
{
T1CONbits.TON = 0;
TMR1 = period;
T1CONbits.TON = 1;
}

And secondly let's say I want to change the overflow time with the PR1 register instead of TMR1 register . Do I have to clear the value in TMR1 when the timer overflows , so it doesnt keep counting until the 0xFFFF value then count up to the value in PR1 register ?

And lastly there is a paragraph in application note (DS70362  , Page 10) that says :

The prescaler counter is cleared when any of the following occurs:
• A write to the Timer register (TMRx) or Timer Control (TxCON) register
• Clearing the Timer Enable (TON) bit in the Timer Control (TxCON<15>) register
• Any device Reset

So does that mean I have to write to the TCKPS<1:0>: (Timer Input Clock Prescale Select bits ) register whenever I update the TMR1 register or when I turn off and on the peripheral ?