Diff: NMEA0183.cpp

Revision:

0:a6e68073c162

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/NMEA0183.cpp	Mon Jul 23 12:23:55 2018 +0000
@@ -0,0 +1,45 @@
+#include "NMEA0183.h"
+
+NMEA0183::NMEA0183()
+{
+}
+
+// CheckParity
+// Returns 1 if valid
+int NMEA0183::CheckParity(char *nmea0183_string)
+{
+    // Calculate parity
+    char parity_calculated = 0x00;
+    for (int i = 1; i < strlen(nmea0183_string)-3; i++) {
+        parity_calculated ^= nmea0183_string[i];
+    }
+
+    // Print parity_calculated to string
+//    char parity_calculated_str[3];
+//    snprintf(parity_calculated_str, 3, "%02x", parity_calculated);
+
+    uint8_t len = strlen(nmea0183_string);
+    char parity_given = hex2dec(nmea0183_string[len-2]) * 16 +  hex2dec(nmea0183_string[len-1]);
+
+    // Compare values
+    if (parity_calculated == parity_given) {
+        return 1;
+    }     
+    return 0;
+}
+
+void NMEA0183::SubString(char *s, char *d, int pos, int len) //usage: substring(Src, Dst, Pos, Len);
+{
+//usage: substring(Source, Destination, pos, len);
+    char *t;
+ 
+    s=s+pos;
+    t=s+len;
+    while (s!=t) {
+        *d=*s;
+        s++;
+        d++;
+    }
+    *d='\0';
+}
+