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.
19 lines
696 B
Plaintext
19 lines
696 B
Plaintext
This is _functionally_ identical to the "button-irq-printf"
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example, but has been modified to use some low power features.
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There is a 115200@8n1 console on PA2, which prints a tick count every second,
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and when the user push button is pressed, the time it is held down for is
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timed (in milliseconds)
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Instead of free running timers and busy loops, this version uses the RTC
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module and attempts to sleep as much as possible, including while the button
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is pressed.
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Status
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~~~~~~
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Only very basic power savings are done!
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Current consumption, led off/on, 16Mhz HSI: 2.7mA/5.4mA
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Current consumption, led off/on, 4Mhz HSI: 1.4mA/?.?mA
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Current consumption, led off/on, 4Mhz MSI: 0.9mA/?.?mA
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