21 lines
879 B
Plaintext
21 lines
879 B
Plaintext
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README
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This example demonstrates the following:
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* Configuriong GPIO pins
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* Toggling GPIO pins
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* Setting up and using GPIO interrupts
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* Unlocking protected GPIO pins
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* Controlling the system clock
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* Changing the system clock on the fly
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Flashes the Red, Green and Blue diodes on the board, in order. The system clock
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starts at 80MHz.
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Pressing SW2 toggles the system clock between 80MHz, 57MHz, 40MHz ,20MHz, and
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16MHz by changing the PLL divisor.
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Pressing SW1 bypasses the PLL completely, and runs off the raw 16MHz clock
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provided by the external crystal oscillator.
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The LEDs will toggle at different speeds, depending on the system clock. The
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system clock changes are handled within the interrupt service routine.
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