NRF 52 OLED SSD 1306 SEGGER

RE: NRF 52 OLED SSD 1306 SEGGER

helsing — Mon, 16 Jan 2023 10:25:57 GMT

Sorry for the delay.

Please check out both our nRF Connect SDK guides and our Blog. Also check out our on-demand webinars.

One may also learn from the samples and applications in nRF Connect SDK as well as Zephyr’s Samples and Demos section.

Working with nRF52 Series is also a good starting point as well as Application development.

What kind of architecture and memory issues, specifically? You could open a new case (as this will be a new topic), and we will reply within the next business day.

RE: NRF 52 OLED SSD 1306 SEGGER

DBdani — Thu, 12 Jan 2023 13:50:44 GMT

Hello Helsing

The solution works perfectly. Thank you very Much!

I feel a bit lost with the programming of the device and with zephyr, I have taken the basic course you recommended but I still have a lot of gaps.
Is there NRF documentation at a low level, defining for example architecture and memory issues?
Are there higher level courses for zephyr and NRF?

Thank you

RE: NRF 52 OLED SSD 1306 SEGGER

helsing — Tue, 10 Jan 2023 13:21:16 GMT

Hi Daniel,

I was able to reproduce the issue you are facing, as well as finding a solution.

Things should work if you use the twi driver instead of twim, and in addition remove zephyr,concat-buf-size = <4096>; from the overlay.

The reason is that twim is using DMA but nRF52832 is only able to send a limited amount of bytes. For example nRF52840, nRF5340 and nRF9160 are not affected by this limitation when it comes to writing to these displays. twi is able to output data continuously, although the CPU becomes a bit more occupied as DMA is not used.

Here is the full overlay:

/ {
	chosen {
		zephyr,display = &ssd1306;
	};
};

&pinctrl {
    i2c0_default: i2c0_default {
        group1 {
            psels = <NRF_PSEL(TWIM_SDA, 0, 26)>, 
                <NRF_PSEL(TWIM_SCL, 0, 27)>;     
        };
    };

    i2c0_sleep: i2c0_sleep {
        group1 {
            psels = <NRF_PSEL(TWIM_SDA, 0, 26)>, 
                <NRF_PSEL(TWIM_SCL, 0, 27)>;     
            low-power-enable;
        };
    };
};

arduino_i2c: &i2c0 {
	compatible = "nordic,nrf-twi";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;
    
  
	ssd1306: ssd1306@3c {
		compatible = "solomon,ssd1306fb";
		reg = <0x3c>;
		width = <128>;
		height = <64>;
		segment-offset = <0>;
		page-offset = <0>;
		display-offset = <0>;
		multiplex-ratio = <63>;
		segment-remap;
		com-invdir;
		prechargep = <0x22>;
	};
};

Attached is the working project I tested, using nRF Connect SDK v2.1.2.

devzone.nordicsemi.com/.../lvgl_2D00_20230110.zip

If you are using nRF Connect SDK v2.2.0 or later you might need to update the overlay with the below code, due to the new naming format. This section of code becomes included when using the shield, so it is not really necessary to include it in the overlay, and could be removed.

/ {
	chosen {
		zephyr,display = &ssd1306_ssd1306_128x64;
	};
};

RE: NRF 52 OLED SSD 1306 SEGGER

DBdani — Mon, 09 Jan 2023 06:39:11 GMT

Hello,

I believe there is nothing to indicate the use of colors in the standard example. Please correct me if I am wrong. I still cannot use the screen correctly.

The numbers do indeed advance, the problem is that they look wrong, with the screen full of random white pixels.

Thank you

/*
 * Copyright (c) 2018 Jan Van Winkel <jan.van_winkel@dxplore.eu>
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#include <zephyr/drivers/display.h>
#include <zephyr/drivers/gpio.h>
#include <lvgl.h>
#include <stdio.h>
#include <string.h>
#include <zephyr/kernel.h>

#define LOG_LEVEL CONFIG_LOG_DEFAULT_LEVEL
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(app);

static uint32_t count;

#ifdef CONFIG_GPIO
static struct gpio_dt_spec button_gpio = GPIO_DT_SPEC_GET_OR(
		DT_ALIAS(sw0), gpios, {0});
static struct gpio_callback button_callback;

static void button_isr_callback(const struct device *port,
				struct gpio_callback *cb,
				uint32_t pins)
{
	ARG_UNUSED(port);
	ARG_UNUSED(cb);
	ARG_UNUSED(pins);

	count = 0;
}
#endif

void main(void)
{
	int err;
	char count_str[11] = {0};
	const struct device *display_dev;
	lv_obj_t *hello_world_label;
	lv_obj_t *count_label;

	display_dev = DEVICE_DT_GET(DT_CHOSEN(zephyr_display));
	if (!device_is_ready(display_dev)) {
		LOG_ERR("Device not ready, aborting test");
		return;
	}

#ifdef CONFIG_GPIO
	if (device_is_ready(button_gpio.port)) {
		err = gpio_pin_configure_dt(&button_gpio, GPIO_INPUT);
		if (err) {
			LOG_ERR("failed to configure button gpio: %d", err);
			return;
		}

		gpio_init_callback(&button_callback, button_isr_callback,
				   BIT(button_gpio.pin));

		err = gpio_add_callback(button_gpio.port, &button_callback);
		if (err) {
			LOG_ERR("failed to add button callback: %d", err);
			return;
		}

		err = gpio_pin_interrupt_configure_dt(&button_gpio,
						      GPIO_INT_EDGE_TO_ACTIVE);
		if (err) {
			LOG_ERR("failed to enable button callback: %d", err);
			return;
		}
	}
#endif

	if (IS_ENABLED(CONFIG_LV_Z_POINTER_KSCAN)) {
		lv_obj_t *hello_world_button;

		hello_world_button = lv_btn_create(lv_scr_act());
		lv_obj_align(hello_world_button, LV_ALIGN_CENTER, 0, 0);
		hello_world_label = lv_label_create(hello_world_button);
	} else {
		hello_world_label = lv_label_create(lv_scr_act());
	}

	lv_label_set_text(hello_world_label, "Hello world!");
	lv_obj_align(hello_world_label, LV_ALIGN_CENTER, 0, 0);

	count_label = lv_label_create(lv_scr_act());
	lv_obj_align(count_label, LV_ALIGN_BOTTOM_MID, 0, 0);

	lv_task_handler();
	display_blanking_off(display_dev);


}

RE: NRF 52 OLED SSD 1306 SEGGER

ovrebekk — Tue, 03 Jan 2023 12:40:06 GMT

Hi Daniel

Sorry for the slow response. We have had limited staffing over Christmas. Håkon is currently unavailable and I will help you out in the mean time.

Are you just running the standard lvgl example without any changes?

Do you see the number getting updated, and can you read it correctly?

If I am not mistaken the standard example is not black and white, and the issues you see might just be caused by the black and white conversion. If this is the case it should be enough to ensure that all the LVGL elements are either black or white, rather than some other colors.

Best regards
Torbjørn

RE: NRF 52 OLED SSD 1306 SEGGER

DBdani — Fri, 23 Dec 2022 06:55:08 GMT

Hello Helsing

Thank you very much for your help.

Now, i can flash DK board, but i have any mistake, because the thisplay show this:

GND-->GND

VCC -->VCC

SCL-->P0.27

SDA-->P0.26

I have this Structure now:

With this code:

(Overlay file)

&pinctrl {
    i2c0_default: i2c0_default {
        group1 {
            psels = <NRF_PSEL(TWIM_SDA, 0, 26)>,
                <NRF_PSEL(TWIM_SCL, 0, 27)>;
        };
    };

    i2c0_sleep: i2c0_sleep {
        group1 {
            psels = <NRF_PSEL(TWIM_SDA, 0, 26)>,
                <NRF_PSEL(TWIM_SCL, 0, 27)>;
            low-power-enable;
        };
    };
};

arduino_i2c: &i2c0 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;   
    zephyr,concat-buf-size = <4096>;
  
    ssd1306: ssd1306@3c {
        compatible = "solomon,ssd1306fb";
        reg = <0x3c>; //0x3c is the i2c address of the SSD1306 aIC.
        width = <128>;
        height = <64>; // Change to '64' when using the 128x64 pixel version.
        segment-offset = <0>;
        page-offset = <0>;
        display-offset = <0>;
        multiplex-ratio = <63>; //change to '63' when using the 128x64 pixel version
        segment-remap;
        com-invdir;
        com-sequential;
        prechargep = <0x22>;
    };
};

Cmakelist

# SPDX-License-Identifier: Apache-2.0

cmake_minimum_required(VERSION 3.20.0)
set(SHIELD ssd1306_128x64)

find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
project(lvgl)

FILE(GLOB app_sources src/*.c)
target_sources(app PRIVATE ${app_sources})

Thank you very much

RE: NRF 52 OLED SSD 1306 SEGGER

helsing — Wed, 21 Dec 2022 12:11:26 GMT

Have you taken the shield into use? I am getting a similar error as you if I remove references to the ssd1306 shield. Try adding this line of code to the file CMakeLists.txt in your project folder: set(SHIELD ssd1306_128x32).

Add the line just below cmake_minimum_required(VERSION 3.20.0).

RE: NRF 52 OLED SSD 1306 SEGGER

DBdani — Tue, 20 Dec 2022 10:10:12 GMT

Hello Helsing,

Thank you for your reply

I try to generate overlay file, and now i have two new problems:

I'm lost with this issue.

Thank you very much

RE: NRF 52 OLED SSD 1306 SEGGER

helsing — Mon, 19 Dec 2022 15:40:56 GMT

I was able to reproduce the same or similar errors when trying to build without any overlay file.

Did you create any .overlay file? Check under input files if there is any such file.

If not present, click where it says "Click to generate overlay". Then add the following to the generated(empty) file:

&pinctrl {
    i2c0_default: i2c0_default {
        group1 {
            psels = <NRF_PSEL(TWIM_SDA, 0, 26)>,
                <NRF_PSEL(TWIM_SCL, 0, 27)>;
        };
    };

    i2c0_sleep: i2c0_sleep {
        group1 {
            psels = <NRF_PSEL(TWIM_SDA, 0, 26)>,
                <NRF_PSEL(TWIM_SCL, 0, 27)>;
            low-power-enable;
        };
    };
};

arduino_i2c: &i2c0 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;   
    zephyr,concat-buf-size = <4096>;
  
    ssd1306: ssd1306@3c {
        compatible = "solomon,ssd1306fb";
        reg = <0x3c>; //0x3c is the i2c address of the SSD1306 aIC.
        width = <128>;
        height = <32>; // Change to '64' when using the 128x64 pixel version.
        segment-offset = <0>;
        page-offset = <0>;
        display-offset = <0>;
        multiplex-ratio = <31>; //change to '63' when using the 128x64 pixel version
        segment-remap;
        com-invdir;
        com-sequential;
        prechargep = <0x22>;
    };
};

I selected i2c0 for nRF52 DK.

Please report back how this goes.

I tried building with nRF Connect SDK v2.1.2 but I did test it on the DK as I did not have any nRF52 DK at hand today. I will try flashing the board tomorrow.

RE: NRF 52 OLED SSD 1306 SEGGER

DBdani — Thu, 15 Dec 2022 13:36:03 GMT

Hello Helsing,

From the recommendations I am using visual studio with zephyr, and I have done the recommended tutorial.

I am trying to compile the code in your post to use oled and I am getting compile errors.

the console say this

Thank you

RE: NRF 52 OLED SSD 1306 SEGGER

helsing — Wed, 14 Dec 2022 11:15:12 GMT

[quote user="DBdani"]Can i use this example with segger Embedded Studio?[/quote]

Yes. You can use the example regardless of whether you choose to use Segger Embedded Studio, Visual Studio Code or command line. For building applications, Visual Studio Code with the nRF Connect for VS Code extension is our recommendation. For more information about the extension, see the nRF Connect for Visual Studio Code documentation page.

[quote user="DBdani"]¿What advantage have nRF Connect SDK?[/quote]

nRF Connect SDK is our main SDK onward while the nRF5 SDK is in maintenance mode. Please see the nRF Connect SDK and nRF5 SDK statement for details. Which SDK you choose is up to you, however, we recommend nRF Connect SDK for all new projects as this is the SDK where fixes, updates and new features will be implemented.

Also see the Introduction page at nRF Connect SDK documentation for details about nRF Connect SDK. Check out the getting started page for nRF Connect SDK as well as the mentioned Nordic Developer Academy.

RE: NRF 52 OLED SSD 1306 SEGGER

DBdani — Tue, 13 Dec 2022 11:50:22 GMT

Hi Hakon

Thank you for your reply.

Can i use this example with segger Embedded Studio? ¿What advantage have nRF Connect SDK?

Thank you

RE: NRF 52 OLED SSD 1306 SEGGER

helsing — Tue, 13 Dec 2022 10:33:04 GMT

Hi Daniel,

We have a blog post on this topic, Printing to an I2C OLED display using nRF Connect SDK. It should be straight forward to use the nRF52 DK, even though it is not mentioned in the post. Please let me know if you need input on how to select pins etc.

I could also recommend Nordic Developer Academy to get started, specifically the course nRF Connect SDK Fundamentals.

[quote user=""]I am using NRF52DK and segger Studio.[/quote]

The above mentioned course goes through Visual Studio Code which is also highly recommended.

Regards,

Håkon