setled.c 2.2 KB

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  1. #include <stdio.h>
  2. #include <stdlib.h>
  3. #include <string.h>
  4. #include <unistd.h>
  5. #include <fcntl.h>
  6. #include <errno.h>
  7. #define DEVICE_PATH "/dev/led"
  8. void usage()
  9. {
  10. printf("Usage: [command] [param1] [param2] [param2]\n");
  11. printf("Commands:\n");
  12. printf(" setled off\n");
  13. printf(" setled red off\n");
  14. printf(" setled green off\n");
  15. printf(" setled red on 1\n");
  16. printf(" setled green on 255\n");
  17. }
  18. int main(int argc, char *argv[])
  19. {
  20. int fd = 0;
  21. int ret = 0;
  22. int blink_value = 0;
  23. char buff[3];
  24. if (argc == 2)
  25. {
  26. if(strcmp(argv[1], "off") == 0)
  27. {
  28. buff[0] = 0x00;
  29. buff[1] = 0x01;
  30. buff[2] = 0x01;
  31. }
  32. }
  33. else if (argc == 3)
  34. {
  35. if(strcmp(argv[1], "red") == 0)
  36. {
  37. buff[0] = 0x40;
  38. }
  39. else if(strcmp(argv[1], "green") == 0)
  40. {
  41. buff[0] = 0x80;
  42. }
  43. else
  44. {
  45. usage();
  46. return -1;
  47. }
  48. if(strcmp(argv[2], "off") == 0)
  49. {
  50. buff[1] = 0x00;
  51. buff[2] = 0x01;
  52. }
  53. else
  54. {
  55. usage();
  56. return -1;
  57. }
  58. }
  59. else if (argc == 4)
  60. {
  61. if(strcmp(argv[1], "red") == 0)
  62. {
  63. buff[0] = 0x40;
  64. }
  65. else if(strcmp(argv[1], "green") == 0)
  66. {
  67. buff[0] = 0x80;
  68. }
  69. else
  70. {
  71. usage();
  72. return -1;
  73. }
  74. if(strcmp(argv[2], "on") == 0)
  75. {
  76. buff[1] = 0x01;
  77. }
  78. else
  79. {
  80. usage();
  81. return -1;
  82. }
  83. blink_value = atoi(argv[3]);
  84. buff[2] = blink_value&0xff;
  85. }
  86. else
  87. {
  88. usage();
  89. return -1;
  90. }
  91. fd = open(DEVICE_PATH, O_RDWR);
  92. if (fd < 0)
  93. {
  94. perror("open failed");
  95. return -1;
  96. }
  97. ret = write(fd, buff, sizeof(buff));
  98. if (ret < 0)
  99. {
  100. perror("write failed");
  101. close(fd);
  102. return -1;
  103. }
  104. close(fd);
  105. return 0;
  106. }