35 lines
1.1 KiB
C
35 lines
1.1 KiB
C
/*
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* PHYS319 Lab3 Timing example in C
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*
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* Written by Ryan Wicks
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* 16 January 2012
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*
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* This program is a C version of the assembly program that formed part of lab 2.
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* This is not the best way to implement timing, or to organize your code.
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* It is simply one way.
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*
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* This will almost certainly not give exactly the same timing as the assembly
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* program from lab 2, and the output assembly will also be very different, even
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* though the task is similar.
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*/
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#include <msp430.h>
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void main(void) {
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volatile unsigned int count; // You must declare your variables in C
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// notice the label volatile. What happens if you remove this label?
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WDTCTL = WDTPW + WDTHOLD; // Stop WDT
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P1DIR = 0x41; // Set P1 output direction
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P1OUT = 0x01; // Set the output
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while (1) { // Loop forever
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for (unsigned char i = 0; i < 2; i++) {
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count = 60000;
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while (count != 0) {
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count--; // decrement
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}
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}
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P1OUT = P1OUT ^ 0x41; // bitwise xor the output with 0x41
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}
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}
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