17 lines
767 B
Plaintext
17 lines
767 B
Plaintext
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See the top level README for information on where to find documentation
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for the raspberry pi and the ARM processor inside. Also find information
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on how to load and run these programs.
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This example is for the older pi boards, see other directories for
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other flavors of raspberry pi.
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This example uses the free running ARM timer, not the 64 bit system
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timer as in blinker02 but the so called ARM timer. In free running mode
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which is a little different from blinker04 which uses the timer mode.
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The system clock appears to come up at 250MHz as documented. Divide that
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by 250 to get 1Mhz on this free running ARM timer. Then count to four
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million ticks between LED state changes and the led will change state
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every four seconds. Count to 20 million, 20 seconds.
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