Add CRC16 with reverse bit order

[metawatch.git] / metawatch.c

diff --git a/metawatch.c b/metawatch.c
index 7305b033e9ab1f3e7b40c2a988810037b8f75d14..c6914ce7249706d063f475d421b431e0bf569db7 100644 (file)
--- a/metawatch.c
+++ b/metawatch.c
@@ -7,23 +7,90 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
+#include <string.h>
+#include <time.h>
 
 #include "metawatch_protocol.h"
+#include "crc16ccitt.h"
+
+
+void dump_frame(unsigned char *frame, int len)
+{
+  int i;
+  for (i=0; i<len; i++)
+    fprintf(stderr, "0x%02x ", frame[i]);
+  fprintf(stderr, "\n");
+}
+
+
+void mw_send_packet(int mw_fd, unsigned char msg_type, unsigned char options, unsigned char *data, unsigned char len)
+{
+  unsigned short crc;
+  unsigned char frame[64];
+
+  memset(frame, 0, 64);
+  frame[0] = MW_SOF;
+  frame[1] = len + 6;
+  frame[2] = msg_type;
+  frame[3] = options;
+  memcpy(frame+4, data, len);
+  
+  crc = crc16ccitt(frame, len+4);
+  *(unsigned short *)(frame+len+4) = crc;
+
+  dump_frame(frame, len+6);
+
+  write(mw_fd, frame, len+6);
+}
+
+void mw_set_rtc(int mw_fd, unsigned char clk1224, unsigned char date_fmt)
+{
+  time_t mtime;
+  struct tm mtm;
+  unsigned short year;
+  unsigned char data[32];
+  
+  mtime = time(NULL);
+  localtime_r(&mtime, &mtm);
+
+  year = mtm.tm_year + 1900;  
+  data[0] = (year & 0x0f00) >> 8;
+  data[1] = (year & 0x00ff);
+  data[2] = mtm.tm_mon + 1;
+  data[3] = mtm.tm_mday;
+  data[4] = mtm.tm_wday;
+  data[5] = mtm.tm_hour;
+  data[6] = mtm.tm_min;
+  data[7] = mtm.tm_sec;
+  data[8] = clk1224;
+  data[9] = date_fmt;
+
+  mw_send_packet(mw_fd, MW_SET_REAL_TIME_CLOCK, 0, data, 10);
+}
+
 
 int main(int argc, char **argv)
 {
-  int mwfd;
+  int mw_fd;
 
   if (argc != 2) {
     fprintf(stderr, "Usage:\n\t%s <devicename>\n", argv[0]);
     return 1;
   };
   
-  mwfd = open(argv[1], O_RDWR);
-  if (mwfd < 0) {
+  crc16ccitt_init();
+
+  mw_fd = open(argv[1], O_RDWR);
+  if (mw_fd < 0) {
     perror("open");
     return 1;
   };
 
+  mw_set_rtc(mw_fd, MW_RTC_CLOCK_24HR, MW_RTC_DATE_DDMM);
+
+  fsync(mw_fd);
+
+  close(mw_fd);
+
   return 0;
 };