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hi
i am testing timer Interrupt
1. environment
kit : CY8CKIT-042-BLE-A
mcu : CY8C4248LQI-BL583 ( PSOC4 )
Psoc Creator 4.1
2. Timer Setting
Clock input - 12MHz
Period - 48,000
On terminal count
Timer pulse toggle : every 4ms --> Oscillocope CH1 - Yellow
3. Function Generator pulse toggle : every 5ms --> Oscillocope CH4 - Green
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problem
I want precise pulses but there is a time delay
50us delay per pulse
How to make precise pulses?
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Solved! Go to Solution.
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There are two issues.
1) The Timer component counts the 12MHz clock from ZERO to 48000. So, the period of the timer is 48,001 If you want to get a 48,000 cycle period result, 47999 should be set to the period value.
2) In your project, you are using the 48MHz IMO as the HFCLK clock which is used as the source clock of the 12MHz clock.
The accuracy of the IMO is +/-2%. So, the accuracy of the 12MHz is +/-2% too.
If you want to generate more accurate Timer interrupt, Use the External Crystal Oscillator (ECO) clock as the HFCLK.
Now, You can use more accurate 24MHz clock as the HFCLK.
Regards,
Noriaki
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There are two issues.
1) The Timer component counts the 12MHz clock from ZERO to 48000. So, the period of the timer is 48,001 If you want to get a 48,000 cycle period result, 47999 should be set to the period value.
2) In your project, you are using the 48MHz IMO as the HFCLK clock which is used as the source clock of the 12MHz clock.
The accuracy of the IMO is +/-2%. So, the accuracy of the 12MHz is +/-2% too.
If you want to generate more accurate Timer interrupt, Use the External Crystal Oscillator (ECO) clock as the HFCLK.
Now, You can use more accurate 24MHz clock as the HFCLK.
Regards,
Noriaki
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thanks Noriaki
It works well.
I understood about clock system