128x64 OLED screen SPI 4 wires with nrf51822 initialisation problem ???

[Raidensama]

Hi, I'm working on a ssd1306 oled screen with the nrf51822 microcontroler and I think I've got initialisation problem judging from this picture

[Raidensama]

I'm using the u8g2 library, if somebody knows what happens help me please. I think I'm really close to make this works.

[fwachsmuth]

Try the SH1106. I had versions of this display that were sold as SSD1306 but actually had a SH1106 on them.

[Raidensama]

Thanks for your reply, I tried it but it didn't work...

[micooke]

Hey @Raidensama are you sure thats a 128x32? It looks like a 128x64

[Raidensama]

No it's a 128x64 I made a mistake in the title...

[micooke]

Hmm, post your initialisation routine please. Also, check that the pins are correct - particularly the reset pin. The nrf gpio pinmapping can be a bit wierd.. Oh yeah, and please confirm you are using the waveshare ble400 variant (assuming you are using sandeeps variants and ble core)

[Raidensama]

This screen doesn't have reset pin... This is how I start the program: u8g2_Setup_ssd1306_128x64_noname_f(&u8g2, U8G2_R0, u8x8_HW_com_nrf51822, u8g2_nrf_gpio_and_delay_cb); //Disply config u8g2_InitDisplay(&u8g2); u8g2_SetPowerSave(&u8g2,0);

And this is my function: uint8_t u8x8_HW_com_nrf51822(u8x8_t u8x8, uint8_t msg, uint8_t arg_int, void arg_ptr) {

uint8_t *data;

switch(msg) {

case U8X8_MSG_BYTE_SEND: data = (uint8_t *)arg_ptr;

 APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi, data, 1, NULL, 0));

break;

case U8X8_MSG_BYTE_INIT:

    ;
nrf_drv_spi_config_t spi_config = NRF_DRV_SPI_DEFAULT_CONFIG;
            spi_config.ss_pin   = SPIM0_SS_PIN;
            spi_config.miso_pin = SPIM0_MISO_PIN;
            spi_config.mosi_pin = SPIM0_MOSI_PIN;
            spi_config.sck_pin  = SPIM0_SCK_PIN;
            spi_config.frequency = NRF_DRV_SPI_FREQ_1M;
            APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, NULL));

            nrf_gpio_cfg_output(DC_PIN);

            break;

case U8X8_MSG_BYTE_SET_DC: //Pin Data/Comand

            nrf_gpio_pin_write(DC_PIN, arg_int);
            break;

default: return 0; } return 1;

}

[Raidensama]

I tried it in debug mode and I saw that the bytes are sent in the right order but my screen displayed this... And the function to switch on the screen (u8g2_SetPowerSave(&u8g2,0)) works as you can see in the picture that means my SPI connections are good right?

[Raidensama]

And Yes I'm using the ble400 waveshare

[micooke]

data = (uint8_t *)arg_ptr;

 APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi, data, 1, NULL, 0));

Just a note that data with its typecasting should not be needed

Also, i think it should be (note the tx length) APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi, arg_ptr, arg_int, NULL, 0));

I remember having something like this happen when i didnt set the reset pin correctly - but you don't have one so that's not the issue.

Although i dont think its the issue, what does your u8g2_nrf_gpio_and_delay_cb function look like?

Otherwise maybe try the Arduino version of the u8g2 library, if that works then its likely something minor in this code. Otherwise its likely a different chipset or some other issue.

[Raidensama]

This my gpio and delay function uint8_t u8g2_nrf_gpio_and_delay_cb(u8x8_t u8x8, uint8_t msg, uint8_t arg_int, void arg_ptr) { switch(msg) { // Initialize the GPIO and DELAY HAL functions. If the pins for DC and RESET have been // specified then we define those pins as GPIO outputs.

case U8X8_MSG_DELAY_MILLI: nrf_delay_ms(arg_int); break;

case U8X8_MSG_DELAY_10MICRO: nrf_delay_us(10*arg_int); break;

default:

u8x8_SetGPIOResult(u8x8, 1); // default return value break; } return 1;

}

I tried without casting and it didn't work

[micooke]

Did you try passing arg_int instead of 1 as per my previous message? If you did then Im all out of ideas, sorry :pensive:

[Raidensama]

I tried this too... I'm waiting for another screen with a reset pin this time. And I will retry with this one.

[micooke]

Goodluck :+1:

[Raidensama]

Thank you @micooke

[Raidensama]

I kept the changes you mentioned and I tried with an other OLED screen which has a reset pin and it works. I add the reset pin in my function u8g2_nrf_gpio_and_delay_cb

[olikraus]

looks good :-)

[micooke]

Awesome!

[acharyanachiket]

Can you share your code and library. Because I am hard time with oled sh1106 who shows images at times and at times it's completely blurry ..Trying to figure out of its a reset pin issue of spi clk

[micooke]

This is my screen test example https://github.com/micooke/arduino-nRF5-smartwatches/blob/master/libraries/examples/Examples/u8g2_ScreenTest/u8g2_ScreenTest.ino

Sounds like you have a dodgy wire connection - likely the ground.

[acharyanachiket]

Thank you let me have check the connections.