25 lines
478 B
C
25 lines
478 B
C
/*
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* Example of polling general purpose i/o pins.
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*/
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#include <fcntl.h>
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#include <sys/gpio.h>
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main ()
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{
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int fd, pnum, value;
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fd = open ("/dev/porta", O_RDWR);
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if (fd < 0) {
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perror ("/dev/porta");
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return -1;
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}
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for (pnum=0; pnum<7; pnum++) {
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value = ioctl (fd, GPIO_POLL | GPIO_PORT (pnum), 0);
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if (value < 0)
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perror ("GPIO_POLL");
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printf ("port%c = 0x%04x\n", pnum + 'A', value);
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}
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return 0;
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}
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