timer1 in oic16f877
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timer1 in oic16f877
what registers are needed to be controlled else than t1con register to control timer1 in pic 16f877,do i need to control register intcon register or PIE ????to get time fro timer 1
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Re: timer1 in oic16f877
t1con contains all the control bits necessary to enable and configure the basic operation of timer 1 (select the clock source and prescaler). The count value is available in the tmr1h:tmr1l register pair.
The pie register is only used if timer interrupts are required.
The pie register is only used if timer interrupts are required.
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Re: timer1 in pic16f877
wow
thanks for the very fast reply...
i have posted this question before,,,so am sorry if this is not appropriate http://matrixmultimedia.com/mmforums/vi ... f=5&t=4101
still cant get anything from my SRF05 sensor
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
i did as mentioned in the linked post step by step but still nothing is working
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
this is what i did using pic16f877 and 8 mhz crystal
1. Turn Sensor Pwr Hi
Delay for 100ms
2.C-code Containing
tmr1h=FCV_CAPTUREH; load pic tmr1h,tmr1l in flowcode
tmr1l=FCV_CAPTUREL;
3. Output 1 to the INIT pin
delay_us(10);or 20 micro seconds
4. C Icon contain g,initialize timer1 to zero
tmr1h = 0x00;
tmr1l = 0x00;
5. Wait for ECHO pin to go high
6. t1con = 0x3B; Start timer counting with 1 : 8 prescalar
7.Keep counting while ECHO pin is high (LOOP)
8. ECHO pin becomes LOW>>>>>C Icon containg
t1con.0 = 0; //Stop Timer1 Counting
FCV_CAPTUREH = tmr1h;get tmr1h value
FCV_CAPTUREL = tmr1l;get tmr1l value
9.Distance = ( ( CaptureH << 8 ) + CaptureL )/58, calculate distance in cm >>(distance is an integer)
10. Output a 0 to the INIT pin
11.delay 100 Milli seconds
12.Repeat again
Timer period= 262140 micro seconds = almost 1/3 second so there is no need for tmr1 overflow because the sensor will lower its echo before timer1 overflows 30milli seconds after echo goes high
so am i missing something here
![Exclamation :!:](./images/smilies/icon_exclaim.gif)
![Shocked :shock:](./images/smilies/icon_eek.gif)
![Shocked :shock:](./images/smilies/icon_eek.gif)
i have posted this question before,,,so am sorry if this is not appropriate http://matrixmultimedia.com/mmforums/vi ... f=5&t=4101
still cant get anything from my SRF05 sensor
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
i did as mentioned in the linked post step by step but still nothing is working
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
![Crying or Very sad :cry:](./images/smilies/icon_cry.gif)
this is what i did using pic16f877 and 8 mhz crystal
1. Turn Sensor Pwr Hi
Delay for 100ms
2.C-code Containing
tmr1h=FCV_CAPTUREH; load pic tmr1h,tmr1l in flowcode
tmr1l=FCV_CAPTUREL;
3. Output 1 to the INIT pin
delay_us(10);or 20 micro seconds
4. C Icon contain g,initialize timer1 to zero
tmr1h = 0x00;
tmr1l = 0x00;
5. Wait for ECHO pin to go high
6. t1con = 0x3B; Start timer counting with 1 : 8 prescalar
7.Keep counting while ECHO pin is high (LOOP)
8. ECHO pin becomes LOW>>>>>C Icon containg
t1con.0 = 0; //Stop Timer1 Counting
FCV_CAPTUREH = tmr1h;get tmr1h value
FCV_CAPTUREL = tmr1l;get tmr1l value
9.Distance = ( ( CaptureH << 8 ) + CaptureL )/58, calculate distance in cm >>(distance is an integer)
10. Output a 0 to the INIT pin
11.delay 100 Milli seconds
12.Repeat again
Timer period= 262140 micro seconds = almost 1/3 second so there is no need for tmr1 overflow because the sensor will lower its echo before timer1 overflows 30milli seconds after echo goes high
so am i missing something here
![Question :?:](./images/smilies/icon_question.gif)
![Question :?:](./images/smilies/icon_question.gif)
![Exclamation :!:](./images/smilies/icon_exclaim.gif)
![Exclamation :!:](./images/smilies/icon_exclaim.gif)
![Exclamation :!:](./images/smilies/icon_exclaim.gif)
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