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Title:PIC16F877A TIMER1定时操作
Author:hnrain
Date:2010-12-28 使用前置分频器
T1CKPS1 T1CKPS1
0 0 1 分频 TMR1时钟为晶振时钟/(4*1)
0 1 2 分频 TMR1时钟为晶振时钟/(4*2)
1 0 4 分频 TMR1时钟为晶振时钟/(4*4)
1 1 8 分频 TMR1时钟为晶振时钟/(4*8)
TMR1是16位宽度的TMR1由2个8位的可读写的寄存器TMR1H和TMR1L组成。 TMR1有专门的启停控制位TMR1ON,通过软件可以任意启动或暂停TMR1计数功能。 T1CON:TIMER1 CONTROL REGISTER bit7-6 unimplemented :Read as ‘0’ bit5-4 T1CKPS1:T1CKPS0:Timer1 input Clock Prescale Select bits 11=1:8 prescale value 10=1:4 prescale value 01=1:2 prescale value 00=1:1 prescale value bit3 T1OSCEN:Timer1 Oscillator Enable Control bit 1 = Oscillator is enable 0 = Oscillator is shut-off bit2 T1SYNC:Timer1 External Clock Input Synchronization Control bit when TMR1CS = 1 1= Do not synchronize external clock input 0= Synchronize external clock input when TMR1CS = 0 This bit is ignored .Timer1 uses the internal clock when TMR1CS = 0. bit1 TMR1CS:Timer1 Clock Source Select bit 1 = External clock from pin RC0/T1OSO/T1CKI 0 = Internal clock bit0 TMR1ON:Timer1 on bit 1 = enables timer1 0 = stops timer1
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