I just noted that the reference page for "char" (Char.html) has a link to "ASCII chart" (ASCIIchart.html).
Characters are stored as numbers however. You can see the specific encoding in the ASCII chart. This means that it is possible to do arithmetic on characters, in which the ASCII value of the character is used (e.g. 'A' + 1 has the value 66, since the ASCII value of the capital letter A is 65). See Serial.println reference for more on how characters are translated to numbers.
The on-line version of the reference includes that page.
The one in the installation package does not.
Also i note that the reference includes this paragraph:
The char datatype is a signed type, meaning that it encodes numbers from -128 to 127. For an unsigned, one-byte (8 bit) data type, use the byte data type.
So decimal values on the second page should all be negative, yes ??
Somehow that just does not seem right.
void setup()
{ char buffer[34];
Serial.begin (9600);
for (int i= 192; i< (224); i++)
{ Serial.print(char(i));
}
Serial.println("");
Serial.println("================================");
for (int i= -64; i< -32; i++)
{ Serial.print(char(i));
}
Serial.println("");
Serial.println("================================");
for (int i= 0; i<32; i++)
{ buffer[i]= (192+i & 0xFF);
Serial.print(" ");
}
buffer[32]=0;
Serial.println(buffer);
Serial.println(buffer[31],DEC);
// Serial.println("================================");
// for (int i= 0; i<32; i++)
// { buffer[i]= (-64+i & 0xFF);
// }
// buffer[32]=0;
// Serial.println(buffer);
for (int i= 0; i<8; i++)
{ Serial.print(buffer[i], DEC);
Serial.print(" ");
}
Serial.println("");
for (int i= 0; i<8; i++)
{ Serial.print(buffer[i], HEX);
Serial.print(" ");
}
Serial.println("");
for (int i= 0; i<8; i++)
{ Serial.print(buffer[i], BIN);
Serial.print(" ");
}
Serial.println("");
}
void loop(){;} //nada
I will be darned if I can tell the difference but they all do come back as negative.
This has something to do with char values over 127 wrapping back around to the negative side , yes ??