d9fb4f7401
Add an example using the RTC to help with a lower power design. This is a sister example to the existing "button-irq-printf", which is functionally identical, but uses far less power. There's more tricks that can be done to lower the power even further, but this shows a few of the early steps that can be done, using the RTC wakeup instead of a timer.
36 lines
814 B
Plaintext
36 lines
814 B
Plaintext
* Prints to the screen when the button is pushed/released (irq driven)
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115200@8n1 console on PA2 (tx only)
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* uses basic timer 6 with overflows to generate a 1ms counter (not an ideal
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use, but shows some api methods and can be demoed on the disco board)
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* uses basic timer 7 with the exti interrupts to do ghetto input capture.
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Not as fast or precise as the real input capture modes, but can be used
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on any gpio pin.
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No effort at saving power is made here. Current consumption on the Disco board
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is ~7.5mA when the green tick led is off, and about 10.5mA when it is on.
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example output:
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hi guys!
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TICK 0
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TICK 1
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TICK 2
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Pushed down!
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held: 443 ms
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Pushed down!
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TICK 3
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held: 217 ms
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Pushed down!
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held: 99 ms
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Pushed down!
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TICK 4
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held: 73 ms
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Pushed down!
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held: 60 ms
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TICK 5
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Pushed down!
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held: 98 ms
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Pushed down!
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