° character flipped

[djonasdev]

LCD display type

ssd1306

Steps to reproduce the issue

#include "ssd1306.h"
void setup()
{
    ssd1306_setFixedFont(ssd1306xled_font6x8);
    ssd1306_128x32_i2c_init();    
    ssd1306_clearScreen();
    ssd1306_drawHLine(10 , 2, 118);
    ssd1306_drawHLine(10 , 30, 118);
    ssd1306_printFixed  (0,  8, "100°C", STYLE_NORMAL);
}
void loop(){}

Screenshot

[lexus2k]

Hi

Thank you for using this library. Unfortunately the symbol ° is in extended part of ASCII table and isn't included to ssd1306xled_font6x8 font.
You need to create new font, please refer to https://github.com/lexus2k/ssd1306/wiki/How-to-create-new-font-for-the-library
Let me know if you still have any questions.

[lexus2k]

Hi @dojo90 ,
Have you succeeded in solving the issue?
Let me know.

Thank you

[dehre]

If you're looking for a quick 'n dirty solution, you can:

1. make a copy of ssd1306xled_font6x8
2. replace a character you're not using, eg ', with the bitmap for °
3. use your new font

Here's how it looks:

#include "ssd1306.h"

#define MY_FONT_6X8_LEN 581 // enough memory to hold a copy of ssd1306xled_font6x8
#define APOSTROPHE_IDX 46   // index of ' in ssd1306xled_font6x8

static uint8_t my_font_6x8[MY_FONT_6X8_LEN];

static void initialize_my_font_6x8(void)
{
    uint8_t my_bitmap[] = {0x00, 0x00, 0x06, 0x06, 0x00, 0x00}; // bitmap for °
    memcpy(my_font_6x8, ssd1306xled_font6x8, MY_FONT_6X8_LEN);
    for (size_t i = APOSTROPHE_IDX, j = 0; j < sizeof(my_bitmap); i++, j++)
    {
        my_font_6x8[i] = my_bitmap[j];
    }
}

void setup()
{
    initialize_my_font_6x8();
    ssd1306_setFixedFont(my_font_6x8);

    ssd1306_128x32_i2c_init();    
    ssd1306_clearScreen();
    ssd1306_drawHLine(10 , 2, 118);
    ssd1306_drawHLine(10 , 30, 118);

    // each time you use ', the character ° will be displayed
    ssd1306_printFixed  (0,  8, "101'C", STYLE_NORMAL); 
}

void loop(){}

[djonasdev]

Thank you both for your help,
Unfortunately I only got around to testing it now.

@dehre
I like the quick/dirty version better, but it didn't work or I always had exceptions in the log.. I can't find any errors either.. Have you tested it yourself?

My solution was that I created a my_font_6x8.h file, included it to the project and used it:

extern const uint8_t my_font_6x8[] PROGMEM;
const uint8_t my_font_6x8[] PROGMEM =
{
 0x00, 0x06, 0x08, 0x20,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // sp
  0x00, 0x00, 0x00, 0x2f, 0x00, 0x00, // !
  0x00, 0x00, 0x07, 0x00, 0x07, 0x00, // "
  0x00, 0x14, 0x7f, 0x14, 0x7f, 0x14, // #
  0x00, 0x24, 0x2a, 0x7f, 0x2a, 0x12, // $
  0x00, 0x23, 0x13, 0x08, 0x64, 0x62, // %
  0x00, 0x36, 0x49, 0x55, 0x22, 0x50, // &
  0x00, 0x00, 0x06, 0x06, 0x00, 0x00, // ' => ° see: https://github.com/lexus2k/ssd1306/issues/139
  0x00, 0x00, 0x1c, 0x22, 0x41, 0x00, // (
  0x00, 0x00, 0x41, 0x22, 0x1c, 0x00, // )
  0x00, 0x14, 0x08, 0x3E, 0x08, 0x14, // *
  0x00, 0x08, 0x08, 0x3E, 0x08, 0x08, // +
  0x00, 0x00, 0x00, 0xA0, 0x60, 0x00, // ,
  0x00, 0x08, 0x08, 0x08, 0x08, 0x08, // -
  0x00, 0x00, 0x60, 0x60, 0x00, 0x00, // .
  0x00, 0x20, 0x10, 0x08, 0x04, 0x02, // /
  0x00, 0x3E, 0x51, 0x49, 0x45, 0x3E, // 0
  0x00, 0x00, 0x42, 0x7F, 0x40, 0x00, // 1
  0x00, 0x42, 0x61, 0x51, 0x49, 0x46, // 2
  0x00, 0x21, 0x41, 0x45, 0x4B, 0x31, // 3
  0x00, 0x18, 0x14, 0x12, 0x7F, 0x10, // 4
  0x00, 0x27, 0x45, 0x45, 0x45, 0x39, // 5
  0x00, 0x3C, 0x4A, 0x49, 0x49, 0x30, // 6
  0x00, 0x01, 0x71, 0x09, 0x05, 0x03, // 7
  0x00, 0x36, 0x49, 0x49, 0x49, 0x36, // 8
  0x00, 0x06, 0x49, 0x49, 0x29, 0x1E, // 9
  0x00, 0x00, 0x36, 0x36, 0x00, 0x00, // :
  0x00, 0x00, 0x56, 0x36, 0x00, 0x00, // ;
  0x00, 0x08, 0x14, 0x22, 0x41, 0x00, // <
  0x00, 0x14, 0x14, 0x14, 0x14, 0x14, // =
  0x00, 0x00, 0x41, 0x22, 0x14, 0x08, // >
  0x00, 0x02, 0x01, 0x51, 0x09, 0x06, // ?
  0x00, 0x32, 0x49, 0x59, 0x51, 0x3E, // @
  0x00, 0x7C, 0x12, 0x11, 0x12, 0x7C, // A
  0x00, 0x7F, 0x49, 0x49, 0x49, 0x36, // B
  0x00, 0x3E, 0x41, 0x41, 0x41, 0x22, // C
  0x00, 0x7F, 0x41, 0x41, 0x22, 0x1C, // D
  0x00, 0x7F, 0x49, 0x49, 0x49, 0x41, // E
  0x00, 0x7F, 0x09, 0x09, 0x09, 0x01, // F
  0x00, 0x3E, 0x41, 0x49, 0x49, 0x7A, // G
  0x00, 0x7F, 0x08, 0x08, 0x08, 0x7F, // H
  0x00, 0x00, 0x41, 0x7F, 0x41, 0x00, // I
  0x00, 0x20, 0x40, 0x41, 0x3F, 0x01, // J
  0x00, 0x7F, 0x08, 0x14, 0x22, 0x41, // K
  0x00, 0x7F, 0x40, 0x40, 0x40, 0x40, // L
  0x00, 0x7F, 0x02, 0x0C, 0x02, 0x7F, // M
  0x00, 0x7F, 0x04, 0x08, 0x10, 0x7F, // N
  0x00, 0x3E, 0x41, 0x41, 0x41, 0x3E, // O
  0x00, 0x7F, 0x09, 0x09, 0x09, 0x06, // P
  0x00, 0x3E, 0x41, 0x51, 0x21, 0x5E, // Q
  0x00, 0x7F, 0x09, 0x19, 0x29, 0x46, // R
  0x00, 0x46, 0x49, 0x49, 0x49, 0x31, // S
  0x00, 0x01, 0x01, 0x7F, 0x01, 0x01, // T
  0x00, 0x3F, 0x40, 0x40, 0x40, 0x3F, // U
  0x00, 0x1F, 0x20, 0x40, 0x20, 0x1F, // V
  0x00, 0x3F, 0x40, 0x38, 0x40, 0x3F, // W
  0x00, 0x63, 0x14, 0x08, 0x14, 0x63, // X
  0x00, 0x07, 0x08, 0x70, 0x08, 0x07, // Y
  0x00, 0x61, 0x51, 0x49, 0x45, 0x43, // Z
  0x00, 0x00, 0x7F, 0x41, 0x41, 0x00, // [
  0x00, 0x55, 0x2A, 0x55, 0x2A, 0x55, // 55
  0x00, 0x00, 0x41, 0x41, 0x7F, 0x00, // ]
  0x00, 0x04, 0x02, 0x01, 0x02, 0x04, // ^
  0x00, 0x40, 0x40, 0x40, 0x40, 0x40, // _
  0x00, 0x00, 0x01, 0x02, 0x04, 0x00, // '
  0x00, 0x20, 0x54, 0x54, 0x54, 0x78, // a
  0x00, 0x7F, 0x48, 0x44, 0x44, 0x38, // b
  0x00, 0x38, 0x44, 0x44, 0x44, 0x20, // c
  0x00, 0x38, 0x44, 0x44, 0x48, 0x7F, // d
  0x00, 0x38, 0x54, 0x54, 0x54, 0x18, // e
  0x00, 0x08, 0x7E, 0x09, 0x01, 0x02, // f
  0x00, 0x18, 0xA4, 0xA4, 0xA4, 0x7C, // g
  0x00, 0x7F, 0x08, 0x04, 0x04, 0x78, // h
  0x00, 0x00, 0x44, 0x7D, 0x40, 0x00, // i
  0x00, 0x40, 0x80, 0x84, 0x7D, 0x00, // j
  0x00, 0x7F, 0x10, 0x28, 0x44, 0x00, // k
  0x00, 0x00, 0x41, 0x7F, 0x40, 0x00, // l
  0x00, 0x7C, 0x04, 0x18, 0x04, 0x78, // m
  0x00, 0x7C, 0x08, 0x04, 0x04, 0x78, // n
  0x00, 0x38, 0x44, 0x44, 0x44, 0x38, // o
  0x00, 0xFC, 0x24, 0x24, 0x24, 0x18, // p
  0x00, 0x18, 0x24, 0x24, 0x18, 0xFC, // q
  0x00, 0x7C, 0x08, 0x04, 0x04, 0x08, // r
  0x00, 0x48, 0x54, 0x54, 0x54, 0x20, // s
  0x00, 0x04, 0x3F, 0x44, 0x40, 0x20, // t
  0x00, 0x3C, 0x40, 0x40, 0x20, 0x7C, // u
  0x00, 0x1C, 0x20, 0x40, 0x20, 0x1C, // v
  0x00, 0x3C, 0x40, 0x30, 0x40, 0x3C, // w
  0x00, 0x44, 0x28, 0x10, 0x28, 0x44, // x
  0x00, 0x1C, 0xA0, 0xA0, 0xA0, 0x7C, // y
  0x00, 0x44, 0x64, 0x54, 0x4C, 0x44, // z
  0x00, 0x00, 0x08, 0x77, 0x00, 0x00, // {
  0x00, 0x00, 0x00, 0x7F, 0x00, 0x00, // |
  0x00, 0x00, 0x77, 0x08, 0x00, 0x00, // }
  0x00, 0x10, 0x08, 0x10, 0x08, 0x00, // ~
  0x14, 0x14, 0x14, 0x14, 0x14, 0x14, // horiz lines // DEL
  0x00 /* This byte is required for italic type of font */
};

#include "my_font_6x8.h"

void setup() {
  ssd1306_setFixedFont(my_font_6x8);
}

[dehre]

Hi @dojo90,
I tried the solution myself before posting and worked fine.
However, it does the exact same thing as you did with your my_font_6x8.h file, that is, it makes a copy of the original font and replaces the "bad" character.
So, if the extra header file doesn't bother you, I think you're fine already!