32 lines
504 B
C
32 lines
504 B
C
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// let's write blinky.c
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#define LED_ADDR ((volatile char*)0xC000)
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#define led_write(x) (*LED_ADDR = (x))
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#define CYCLES_PER_MS 6666 // ish
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void busy_sleep_1ms() {
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for (int i = 0; i < CYCLES_PER_MS; ++i) {
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// nothing
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}
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}
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/** waits a general amount of time */
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void busy_sleep(int ms) {
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for (int i = 0; i < ms; ++i) {
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busy_sleep_1ms();
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}
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}
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int main() {
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int onoff = 0;
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while (1) {
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led_write(onoff);
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busy_sleep(100);
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onoff++;
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}
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return 0; // actually unreachable
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}
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