You are indeed correct, on many counts, I think. Try this for writing:
// Function takes a void pointer to data, and how much to write (no other way to know)
// Could also take a starting address, and return the size of the reach chunk, to be more generic
void EEPROM_write(void * data, byte datasize) {
int addr = 0;
EEPROM.write(addr++, datasize);
for (int i=0; i<datasize; i++) {
EEPROM.write(addr++, data[i]);
}
}
You would call it like this:
char[] stringToWrite = "Test";
EEPROM_write(stringToWrite, strlen(stringToWrite));
To read then:
int addr = 0;
byte datasize = EEPROM.read(addr++);
char stringToRead[0x20]; // allocate enough space for the string here!
char * readLoc = stringToRead;
for (int i=0;i<datasize; i++) {
readLoc = EEPROM.read(addr++);
readLoc++;
}
Note that this is not using the String
class developed for Arduino: reading and writing that would be different. But the above should work for char
array strings.
Note however, that while EEPROM_write()
looks generic now, it isn't really, since addr
is harcoded. It can only write data to the beginning of EEPROM.