AP_GPS: remove dedundant crc32 routine from Nova

Author: peterbarker

libraries/AP_GPS/AP_GPS_NOVA.cpp

@@ -176,8 +176,8 @@ AP_GPS_NOVA::parse(uint8_t temp)
             nova_msg.crc += (uint32_t) (temp << 24);
             nova_msg.nova_state = nova_msg_parser::PREAMBLE1;
 
-            uint32_t crc = CalculateBlockCRC32((uint32_t)nova_msg.header.nova_headeru.headerlength, (uint8_t *)&nova_msg.header.data, (uint32_t)0);
-            crc = CalculateBlockCRC32((uint32_t)nova_msg.header.nova_headeru.messagelength, (uint8_t *)&nova_msg.data, crc);
+            uint32_t crc = crc_crc32((uint32_t)0, (uint8_t *)&nova_msg.header.data, (uint32_t)nova_msg.header.nova_headeru.headerlength);
+            crc = crc_crc32(crc, (uint8_t *)&nova_msg.data, (uint32_t)nova_msg.header.nova_headeru.messagelength);
 
             if (nova_msg.crc == crc) {
                 return process_message();
@@ -293,25 +293,4 @@ AP_GPS_NOVA::process_message(void)
     return false;
 }
 
-#define CRC32_POLYNOMIAL 0xEDB88320L
-uint32_t AP_GPS_NOVA::CRC32Value(uint32_t icrc)
-{
-    int i;
-    uint32_t crc = icrc;
-    for ( i = 8 ; i > 0; i-- ) {
-        if ( crc & 1 )
-            crc = ( crc >> 1 ) ^ CRC32_POLYNOMIAL;
-        else
-            crc >>= 1;
-    }
-    return crc;
-}
-
-uint32_t AP_GPS_NOVA::CalculateBlockCRC32(uint32_t length, uint8_t *buffer, uint32_t crc)
-{
-    while ( length-- != 0 ) {
-        crc = ((crc >> 8) & 0x00FFFFFFL) ^ (CRC32Value(((uint32_t) crc ^ *buffer++) & 0xff));
-    }
-    return( crc );
-}
 #endif

libraries/AP_GPS/AP_GPS_NOVA.h

@@ -39,8 +39,6 @@ class AP_GPS_NOVA : public AP_GPS_Backend
 
     bool parse(uint8_t temp);
     bool process_message();
-    uint32_t CRC32Value(uint32_t icrc);
-    uint32_t CalculateBlockCRC32(uint32_t length, uint8_t *buffer, uint32_t crc);
 
     static const uint8_t NOVA_PREAMBLE1 = 0xaa;
     static const uint8_t NOVA_PREAMBLE2 = 0x44;