- improvements in protocols and drivers

binprot.c

@@ -59,7 +59,7 @@ typedef enum {intType, hexType, floatType,
   skipType, codeType, crcType, dumpType, errorType} BinDataType;
 // dumpType, errorType must be the last items
 
-typedef enum {modbusCrc, kellerCrc, syconCrc} CrcAlgorithm;
+typedef enum {modbusCrc, kellerCrc, rsportCrc, syconCrc} CrcAlgorithm;
 
 typedef struct {
   CrcAlgorithm crcAlgorithm;
@@ -104,6 +104,37 @@ static int calc_crc(char *inp, int inpLen)
   }
   return crc;
 }
+/*----------------------------------------------------------------------------*/
+static int calc_crc8(char *inp, int inpLen)
+{
+/** CRC-8 (x8+x5+x4+1) Algorithm
+ * crc calculation:
+ *   returns the 8bit CRC value of a message
+ * crc check:
+ *   returns 0 when the crc appended to the message is correct
+ */
+
+  unsigned char crc = 0;
+  unsigned char data;
+  int n;
+
+  while (inpLen--) {
+    data = *(unsigned char *) inp;
+    for (n = 0; n < 8; n++) {
+      if ((crc ^ data) & 1) {
+        crc ^= 0x18;
+        crc >>= 1;
+        crc |= 0x80;
+      } else {
+        crc >>= 1;
+        crc &= 0x7f;
+      }
+      data >>= 1;
+    }
+    inp++;
+  }
+  return crc;
+}
 
 /*----------------------------------------------------------------------------*/
 int BinReadItem(Ascon *a) {
@@ -250,6 +281,10 @@ int BinHandler(Ascon *a) {
           DynStringConcatChar(dyn, crc % 256);
           DynStringConcatChar(dyn, crc / 256);
           break;
+        case rsportCrc:
+          crc = calc_crc8(GetCharArray(dyn), l);
+          DynStringConcatChar(dyn, crc);
+          break;
         }
       } else if (strncasecmp(item, "int", 3) == 0) {
         sscanf(item + 3, "%d", &size);
@@ -475,6 +510,7 @@ int BinHandler(Ascon *a) {
           str[l-1] = i;
           /* fall through */
         case modbusCrc:
+        case rsportCrc:
           if (calc_crc(str, l) != 0) {
             DynStringConcat(p->result, "badCRC ");
           }
@@ -503,7 +539,7 @@ static int BinInit(Ascon * a, SConnection * con, int argc, char *argv[])
 {
   BinPrivate *p;
 
-/* argv[2] may be modbus-crc (default), keller-crc or sycon-crc */
+/* argv[2] may be modbus-crc (default), keller-crc, rsport-crc or sycon-crc */
   
   if (argc < 2) {
     return 0;
@@ -517,6 +553,8 @@ static int BinInit(Ascon * a, SConnection * con, int argc, char *argv[])
       p->crcAlgorithm = kellerCrc;
     } else if (strcasecmp(argv[2], "sycon-crc") == 0) {
       p->crcAlgorithm = syconCrc;
+    } else if (strcasecmp(argv[2], "rsport-crc") == 0) {
+      p->crcAlgorithm = rsportCrc;
     } else if (strcasecmp(argv[2], "modbus-crc") != 0) {
       SCPrintf(con, eError, "ERROR: unknown crc-algorithm %s", argv[2]);
       a->private = NULL;