Wemos board - serial.read

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1

Hi there - been using a wemos m0 clone, and have troubles using the serialusb.read, when sending 1 over the serial monitor it returns 49 followed by 10....why, works fine with nano or uno...

2

that's correct

49 is the ascii code for the symbol '1'
10 is a line feed

➜ post your code and explain how you configured the serial monitor

3

Thanks for the reply.

int incomingByte = 0 ; // for incoming serial data
#include <SPI.h>
#define Serial SerialUSB
 void setup() {
  while (!SerialUSB);
   SerialUSB.begin(9600); // opens serial port, sets data rate to 9600 bps
SerialUSB.print ("Starting");
SerialUSB.print (x);
inputString.reserve(200);
}

void loop() {
  // send data only when you receive data:
  if (SerialUSB.available() > 0) {
    // read the incoming byte:
    x = SerialUSB.read();
  
    // say what you got:
    SerialUSB.print("I received: ");
    SerialUSB.println(x);
  }
}`
4

that cannot be the code, it would not compile as neither x nor inputString are defined.

5

Check again, it will be the same on Wemos as on Uno/nano. If not, you must be using 2 slightly different codes.

Also explain what, in your mind, "works fine" actually means, because we don't know that.

6

Thanks for the reply, works fine with uno\nano, enter 1, get "I received 1 " back on the serial monitior.

Sorry missed int x, on the code.

7

post the real code. you likely have a type mismatch which makes the Serial print the ASCII value instead of the char

8

Post your corrected code, and the output from serial monitor when you run the code on Uno/Nano, then the output you see with Wemos M0. If you do this accurately, I will use the code to test using my Nano and another SAMD21 board I have, to see if I can repeat your results.

9

Thanks for the help. Note that <no line entered> is selected on serial monitior

int x = 0;
int incomingByte = 0 ; // for incoming serial data
#include <SPI.h>
#define Serial SerialUSB
String inputString = "";         // a String to hold incoming data
bool stringComplete = false; 
void setup() {
 while (!SerialUSB);
  SerialUSB.begin(9600); // opens serial port, sets data rate to 9600 bps
SerialUSB.print ("Starting");
inputString.reserve(200);
}
void loop() {
 // send data only when you receive data:
 if (SerialUSB.available() > 0) {
   // read the incoming byte:
   x = SerialUSB.read();
     // say what you got:
   SerialUSB.print("I received: ");
   SerialUSB.println(x);
 }
}

Wemos reply on the serial monitor

1 entered serial monitir "I received 49",
2 entered serial monitor "I received 50",
3 entered serial monitor "I received 51",
4 entered serial monitor "I received 52",
try serial monitor "I received 116"; "I received 114""I received 121"

nano output, had to take SerialUSB for the nano,
and the the same results !??!! - differnet from the laptop i was using last night !!....``

10

make that a char

char x = 0;

I'm pretty sure you'll also get numbers on a UNO because you are trying to print a number, not a character

the print function is smart - it adapts to the type of parameters you pass. if it's a number it will print the number, if it's a character it prints the character, if it's a pointer to a character - it will assume it's a null terminated char array and will print a string (c-string).

11

Thanks for that it helped.

12

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