Problem outputing to RS-232

Projects Programming
1

Hi,

I am having a problem with a very simple piece of code. I have a Leonardo and a CuteDigi RS232 shield. For debugging, I've attached the serial port to my mac and I'm looking at the output in CoolTerm.

When I write to the SerialConsole (Serial), everything is fine. However, when I write to the UART (Serial1), two bytes are written, both of which make no sense. In this example the output showing up in CoolTerm is: 01 1F. For the life of me I cannot figure out what is going on.

Any ideas?

Thanks,

Carl

void setup() {
    Serial.begin(9600);
    Serial1.begin(9600);
}

void loop() {
    char char_a = 'a';

    Serial.write(char_a); delay(100);
 
    Serial1.write(char_a); delay(100);
}
2 
void setup() {
    Serial.begin(9600);
    Serial.begin(9600);
}

void loop() {
    char char_a = 'a';

    Serial.write(char_a); delay(100);
 
    Serial1.write(char_a); delay(100);
}

Generally, before you can use Serial1.write(), you need to use Serial1.begin(). On the Leonardo, you need to wait for the instance to actually start.

3

Sorry, mistype on entering the code (didn't copy and paste as I am working across two computers). I did initialize Serial1. The correct code is:

void setup() {
   Serial.begin(9600);
   Serial1.begin(9600);
}

Carl

4

Is your CoolTerm (or whatever you're using) set to 9600 baud, 8 data bits, no parity, 1 stop bit, no handshake?