OLED WITH I2C

[vohra alihussain]

I am using nrf52832 and I am trying to interface OLED with it. I am attaching the code below and i referred that code from https://github.com/devdprj/olednrf here,

i made the changes because it has some file missing. I am not getting any character on display and it remains blank. I tried to change address but doesnt works.

#include <stdio.h>
#include "nrf_drv_twi.h"
#include "nrf_delay.h"
#include "i22c.h"
#include "ssd1306.h"
#include "binary.h"


extern uint8_t time_buffer[128];

#define LOGO16_GLCD_HEIGHT 16
#define LOGO16_GLCD_WIDTH  16


static const unsigned char /*PROGMEM*/ logo16_glcd_bmp[] = {
    B00000000, B11000000,
    B00000001, B11000000,
    B00000001, B11000000,
    B00000011, B11100000,
    B11110011, B11100000,
    B11111110, B11111000,
    B01111110, B11111111,
    B00110011, B10011111,
    B00011111, B11111100,
    B00001101, B01110000,
    B00011011, B10100000,
    B00111111, B11100000,
    B00111111, B11110000,
    B01111100, B11110000,
    B01110000, B01110000,
    B00000000, B00110000
};

void testdrawchar(void)
{
    ssd1306_clear_display();
    ssd1306_set_textsize(1);
    ssd1306_set_textcolor(WHITE);
    ssd1306_set_cursor(0, 0);

    for (uint8_t i = 0; i < 168; i++) {
        if (i == '\n') continue;
        ssd1306_write(i);
        if ((i > 0) && (i % 21 == 0))
            ssd1306_write('\n');
    }
    ssd1306_display();
}

void testdrawline(void)
{
    for (int16_t i = 0; i < ssd1306_width(); i += 4) {
        ssd1306_draw_line(0, 0, i, ssd1306_height() - 1, WHITE);
        ssd1306_display();
    }
    for (int16_t i = 0; i < ssd1306_height(); i += 4) {
        ssd1306_draw_line(0, 0, ssd1306_width() - 1, i, WHITE);
        ssd1306_display();
    }
    nrf_delay_ms(250);

    ssd1306_clear_display();
    for (int16_t i = 0; i < ssd1306_width(); i += 4) {
        ssd1306_draw_line(0, ssd1306_height() - 1, i, 0, WHITE);
        ssd1306_display();
    }
    for (int16_t i = ssd1306_height() - 1; i >= 0; i -= 4) {
        ssd1306_draw_line(0, ssd1306_height() - 1, ssd1306_width() - 1, i, WHITE);
        ssd1306_display();
    }
    nrf_delay_ms(250);

    ssd1306_clear_display();
    for (int16_t i = ssd1306_width() - 1; i >= 0; i -= 4) {
        ssd1306_draw_line(ssd1306_width() - 1, ssd1306_height() - 1, i, 0, WHITE);
        ssd1306_display();
    }
    for (int16_t i = ssd1306_height() - 1; i >= 0; i -= 4) {
        ssd1306_draw_line(ssd1306_width() - 1, ssd1306_height() - 1, 0, i, WHITE);
        ssd1306_display();
    }
    nrf_delay_ms(250);

    ssd1306_clear_display();
    for (int16_t i = 0; i < ssd1306_height(); i += 4) {
        ssd1306_draw_line(ssd1306_width() - 1, 0, 0, i, WHITE);
        ssd1306_display();
    }
    for (int16_t i = 0; i < ssd1306_width(); i += 4) {
        ssd1306_draw_line(ssd1306_width() - 1, 0, i, ssd1306_height() - 1, WHITE);
        ssd1306_display();
    }
    nrf_delay_ms(250);

    ssd1306_display();
    nrf_delay_ms(250);
    ssd1306_clear_display();
}


void testdrawbitmap(const uint8_t *bitmap, uint8_t w, uint8_t h)
{
#define NUMFLAKES 10
#define XPOS 0
#define YPOS 1
#define DELTAY 2

    uint8_t icons[NUMFLAKES][3];

    // initialize
    for (uint8_t f = 0; f < NUMFLAKES; f++) {
        icons[f][XPOS] = rand() % ssd1306_width();
        icons[f][YPOS] = 0;
        icons[f][DELTAY] = (rand() % 5) + 1;
    }

    while (1) {
        // draw each icon
        for (uint8_t f = 0; f < NUMFLAKES; f++) {
            ssd1306_draw_bitmap(icons[f][XPOS], icons[f][YPOS], logo16_glcd_bmp, w, h, WHITE);
        }
        ssd1306_display();
        nrf_delay_ms(200);

        // then erase it + move it
        for (uint8_t f = 0; f < NUMFLAKES; f++) {
            ssd1306_draw_bitmap(icons[f][XPOS], icons[f][YPOS],  logo16_glcd_bmp, w, h, BLACK);
            // move it
            icons[f][YPOS] += icons[f][DELTAY];
            // if its gone, reinit
            if (icons[f][YPOS] > ssd1306_height()) {
                icons[f][XPOS] = rand() % ssd1306_width();
                icons[f][YPOS] = 0;
                icons[f][DELTAY] = (rand() % 5) + 1;
            }
        }
    }
}



int main(void)
{
 
        twi_init();
        ssd1306_begin(SSD1306_SWITCHCAPVCC, SSD1306_I2C_ADDRESS, false);
	nrf_delay_ms(1000);
    ssd1306_display();
    nrf_delay_ms(1000);
    testdrawline();
    while (true)
    {
        ssd1306_clear_display();
        // draw a single pixel
        ssd1306_draw_pixel(10, 10, WHITE);
        ssd1306_display();
        nrf_delay_ms(500);

        ssd1306_draw_circle(SSD1306_LCDWIDTH / 2, SSD1306_LCDHEIGHT / 2, 30, WHITE);
        ssd1306_display();
        nrf_delay_ms(500);

        testdrawchar();
        nrf_delay_ms(500);

        ssd1306_clear_display();
        ssd1306_display();
        nrf_delay_ms(500);

        testdrawline();

        ssd1306_clear_display();
        ssd1306_draw_bitmap(30, 16,  logo16_glcd_bmp, 16, 16, 1);
        ssd1306_display();
        nrf_delay_ms(500);

        // draw a bitmap icon and 'animate' movement
        testdrawbitmap(logo16_glcd_bmp, LOGO16_GLCD_HEIGHT, LOGO16_GLCD_WIDTH);

    }
}

[MartinBL]

Are you able to get a response from the OLED screen with the TWI Scanner example? If not you probably have an issue with pin numbering, power supply, or some other HW issue. If yes, you are probably using the SSD1306 drivers wrong. 

[vohra alihussain]

Yes I am able to get response from the OLDE screen..

will you check my code is right or not?

 If yes, you are probably using the SSD1306 drivers wrong. what does it mean?

[MartinBL]

Your code looks pretty much identical to the code in the github repository you linked to, and I assume that should work. 

I don't know anything about the SSD1306 driver and I don't know what OLED screen you are using, but if you are indeed able to get a response form the screen then maybe it is just a matter of power. At least this OLED screen seems to have some special power needs. 

[vohra alihussain]

sir, i checked it and there is no issue of power... it works fine with 3.3v and 5v both on arduino but it doesnt works for my nrf52832?

[MartinBL]

I tested the driver in your link with an OLED screen I found here at the office and I couldn't make it work either. 

Then I tested this code and if I comment out the BLE stuff it works right out of the box (SDK 12.2.0). I suggest you try that one instead. 

[MartinBL]

I tested the driver in your link with an OLED screen I found here at the office and I couldn't make it work either. 

Then I tested this code and if I comment out the BLE stuff it works right out of the box (SDK 12.2.0). I suggest you try that one instead. 

[vohra alihussain]

ok thanks...

if you can suggest what is error in my code??

I will try the code which you have suggest and I will let you know..

[MartinBL]

if you can suggest what is error in my code??
Unfortunately I have no idea.