ASCII decimal value to Quad, alphanumeric display

Components & Accessories Displays
1

I am using the QWIIC ALPHANUMERIC display . How can a ASCII Decimal value be sent to the display.

Using a rotary encoder; position gets assigned an ASCII decimal value. Need to display as the ASCII character.

William

2

[Project code

All segments of digit 0 are ON. ASCII characters ‘O’, ‘O’, ‘O’ display as expected. Variable result is not displaying.

William](Rotary_encoder_and_Alphnumeric_ display.ino · GitHub)

3

Convert what you want to a string then display.print(the_string)

So something like this (untested)

#include <SparkFun_Alphanumeric_Display.h>
HT16K33 display;

void setup() {
  display.begin(); // you should check for an error
}

void loop() {
  static int x = 0;
  print_num(x);
  x++;
  if (x > 9999)
    x = 0;
  delay(1000);
}

void print_num(int num) {
  char buf[5];
  snprintf(buf, sizeof(buf), "%s", num);
  display.print(s);
}
4

This:

snprintf(buf, sizeof(buf), "%s", num);

should be

snprintf(buf, sizeof(buf), "%d", num);
5

How can I use display.printchar(result, 0) to print String character value?

result is the ASCII decimal equitant of the character to be displayed.

William

6

Has the question you asked in the first post been answered? Is the problem solved?

7

getEncoderPosition() returns a 32-bit value. You are assigning that to result (with a bit of math) which is a 16-bit value, then you are assigning that to letter which is an 8-bit value. Are you sure that is a printable value? What I you getting on the serial monitor when you print the value of result?

8

What i found that works:

void display_one(){

  //The input to setBrightness is a duty cycle over 16
  //So, acceptable inputs to this function are ints between 0 (1/16 brightness) and 15 (full brightness)
  display.setBrightness(11);
  
  display.printChar(char(result1), 0);  // when enc = 0 and new_position = 1; result1 displays A 
  display.printChar(char(result2), 1);
  display.printChar(char(result3), 2);
  display.printChar(char(result4), 3);

  display.updateDisplay();

}

[[Gist of complete code

William](Alphanumeric display · GitHub)