esp32-nmea2000-obp60/lib/nmea0183ton2k/GwNmea0183Msg.h

119 lines
4.0 KiB
C++

#pragma once
#include "NMEA0183Msg.h"
class SNMEA0183Msg : public tNMEA0183Msg{
public:
int sourceId;
const char *line;
bool isAis=false;
SNMEA0183Msg(const char *line, int sourceId){
this->sourceId=sourceId;
this->line=line;
int len=strlen(line);
if (len >6){
if (strncasecmp(line,"!AIVDM",6) == 0
||
strncasecmp(line,"!AIVDO",6) == 0
) isAis=true;
}
}
SNMEA0183Msg(){
line=NULL;
}
String getKey(){
if (!isAis) return MessageCode();
if (!line) return String(" ");
char buf[6];
strncpy(buf,line+1,5);
buf[5]=0;
return String(buf);
}
char fromHex(char v){
if (v >= '0' && v <= '9') return v-'0';
if (v >= 'A' && v <= 'F') return v-'A'+10;
if (v >= 'a' && v <= 'f') return v-'a'+10;
return 0;
}
bool SetMessageCor(const char *buf)
{
unsigned char csMsg;
int i = 0;
uint8_t iData = 0;
bool result = false;
Clear();
_MessageTime = millis();
if (buf[i] != '$' && buf[i] != '!')
return result; // Invalid message
Prefix = buf[i];
i++; // Pass start prefix
// Serial.println(buf);
// Set sender
for (; iData < 2 && buf[i] != 0; i++, iData++)
{
CheckSum ^= buf[i];
Data[iData] = buf[i];
}
if (buf[i] == 0)
{
Clear();
return result;
} // Invalid message
Data[iData] = 0;
iData++; // null termination for sender
// Set message code. Read until next comma
for (; buf[i] != ',' && buf[i] != 0 && iData < MAX_NMEA0183_MSG_LEN; i++, iData++)
{
CheckSum ^= buf[i];
Data[iData] = buf[i];
}
if (buf[i] != ',')
{
Clear();
return result;
} // No separation after message code -> invalid message
// Set the data and calculate checksum. Read until '*'
for (; buf[i] != '*' && buf[i] != 0 && iData < MAX_NMEA0183_MSG_LEN; i++, iData++)
{
CheckSum ^= buf[i];
Data[iData] = buf[i];
if (buf[i] == ',')
{ // New field
Data[iData] = 0; // null termination for previous field
if (_FieldCount >= MAX_NMEA0183_MSG_FIELDS){
Clear();
return false;
}
Fields[_FieldCount] = iData + 1; // Set start of field
_FieldCount++;
}
}
if (buf[i] != '*')
{
Clear();
return false;
} // No checksum -> invalid message
Data[iData] = 0; // null termination for previous field
i++; // Pass '*';
csMsg = fromHex(buf[i])<< 4;
i++;
csMsg |= fromHex(buf[i]);
if (csMsg == CheckSum)
{
result = true;
}
else
{
Clear();
}
return result;
}
};