ST75256 128x128 SPI display

[AlexBlows]

Hi.
I'm trying to set up a custom display (ST75256 128x128 SPI HW). I have been using the available 256x128 but when I rotate, I see problems as the buffer size is incorrect. My LCD uses this init sequence: (it's pretty much as per the LCD driver's datasheet example but with customizations)

static const uint8_t u8x8_d_st75256_128x128_init_seq[] = {
    U8X8_START_TRANSFER(),
    U8X8_DLY(10),               // 10ms delay

    U8X8_C(0x30),               // Extension command 1
    U8X8_C(0x6E),               // Enable Master

    U8X8_C(0x31),               // Extension command 2
    U8X8_C(0xD7), U8X8_A(0x9F), // Disable Auto Read
    U8X8_C(0xE0), U8X8_A(0x00), // Enable OTP Read
    U8X8_DLY(10),
    U8X8_C(0xE3),               // OTP Up-Load
    U8X8_DLY(20),               // 20ms delay
    U8X8_C(0xE1),               // OTP Control End

    U8X8_C(0x30),               // Extension command 1
    U8X8_C(0x94),               // Sleep Out
    U8X8_C(0xAE),               // Display Off
    U8X8_DLY(50),               // 50ms delay

    U8X8_C(0x20),               // Power Control  
    U8X8_A(0x0B),               // VB, VR, VF All on
    U8X8_C(0x81), U8X8_A(0x1D), U8X8_A(0x04), // Set Vop (15.0V)

    U8X8_C(0x31),               // Extension command 2
    U8X8_C(0x32), U8X8_A(0x00), // Analog Set
    U8X8_A(0x01),               // Booster efficiency level 1
    U8X8_A(0x02),               // Bias 1/12
    U8X8_C(0x51), U8X8_A(0xFA), // Booster Level x 8

    U8X8_C(0x30),               // Extension command 1
    U8X8_C(0xF0), U8X8_A(0x10), // Display Mode = Monochrome
    U8X8_C(0xCA),               // Display Control
    U8X8_A(0x00),               // CL Dividing Ratio = Not divided
    U8X8_A(0x7F),               // Duty Set = 128
    U8X8_A(0x3F),               
    U8X8_C(0xBC), U8X8_A(0x00), // Data Scan Direction
    U8X8_C(0xA6),               // Normal Display
    U8X8_C(0x0C),               // Data Format = LSB on Top
    U8X8_CAA(0x75, 0x00, 0x7F), // row range for 128 rows
    U8X8_CAA(0x15, 0x00, 0x7F), // col range for 128 cols

    U8X8_C(0x31),               // Extension command 2
    U8X8_C(0x40),               // Internal Power Supply

    U8X8_C(0x30),               // Extension command 1
    U8X8_C(0xaf),               // Display On
    U8X8_END_TRANSFER(),
    U8X8_END()
};

What would be the best approach to getting this custom LCD working? (I need it to work in all 4 viewing directions).
Can it be added to the library?

[olikraus]

i will add this to u8g2, but we probably need to update all the additional information (offset, etc) together.

[olikraus]

I have created beta release 2.36.13 with constructor U8G2_ST75256_128X128_...

I assume the offset needs to be updated:

u8g2/csrc/u8x8_d_st75256.c

Lines 2011 to 2012 in 06d6a72

	/* default_x_offset = */ 0, /* must be 0, because this is checked also for normal mode */
	/* flipmode_x_offset = */ 0, /* used as y offset */

Can you do a test with this code?
Please execute FlipMode.ino example (See example menu in Arduino IDE or here). The flip mode test example will cycle through eight modes. In all modes there must be a solid frame next to the border of the display.

You can download the latest U8g2 beta release from here: https://github.com/olikraus/U8g2_Arduino/archive/master.zip
Arduino IDE:

1. Remove the existing U8g2_Arduino library (https://stackoverflow.com/questions/16752806/how-do-i-remove-a-library-from-the-arduino-environment)
2. Install the U8g2_Arduino Zip file via Arduino IDE, add zip library menu (https://www.arduino.cc/en/Guide/Libraries).

PlatformIO:
platformio.ini (https://docs.platformio.org/en/latest/projectconf/section_env_library.html#lib-deps) should include

lib_deps =
  u8g2=https://github.com/olikraus/U8g2_Arduino/archive/master.zip

[MikeAtETI]

@olikraus I'll be working on verify this for @AlexBlows - give me a few days

[MikeAtETI]

@olikraus it seems to work ok, we're working on an ESP32 so some of the code has been slightly different, but with a loop like this:

  while (1) {
        u8g2_ClearBuffer(&u8g2);
        switch (cs++) {
            case 0:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R0);
                u8g2_SetFlipMode(&u8g2, 0);
                break;
            case 1:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R0);
                u8g2_SetFlipMode(&u8g2, 1);
                break;
            case 2:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R1);
                u8g2_SetFlipMode(&u8g2, 0);
                break;
            case 3:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R1);
                u8g2_SetFlipMode(&u8g2, 1);
                break;
            case 4:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R2);
                u8g2_SetFlipMode(&u8g2, 0);
                break;
            case 5:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R2);
                u8g2_SetFlipMode(&u8g2, 1);
                break;
            case 6:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R3);
                u8g2_SetFlipMode(&u8g2, 0);
                break;
            case 7:
                u8g2_SetDisplayRotation(&u8g2, U8G2_R3);
                u8g2_SetFlipMode(&u8g2, 1);
                cs = 0;
                break;
        }
        snprintf(buffer,
                 sizeof(buffer),
                 "%.2f\xB0"
                 "C",
                 DEVICE.channels[0].current_reading.value);

        u8g2_DrawStr(&u8g2, 10, 69, buffer);

        u8g2_SendBuffer(&u8g2);
        vTaskDelay(pdMS_TO_TICKS(1000));
    }

and an initialisation like

 // Configure HAL
  static u8g2_esp32_hal_t u8g2_hal = U8G2_ESP32_HAL_DEFAULT;
  u8g2_hal.bus.spi.clk = PIN_CLK;
  u8g2_hal.bus.spi.mosi = PIN_MOSI;
  u8g2_hal.bus.spi.cs = PIN_CS;
  u8g2_hal.dc = PIN_DC;
  u8g2_hal.reset = PIN_RESET;
  u8g2_esp32_hal_init(u8g2_hal);

  u8g2_Setup_st75256_128x128_f(&u8g2, U8G2_R0, u8g2_esp32_spi_byte_cb,
                               u8g2_esp32_gpio_and_delay_cb);

  // u8g2_Setup_st75256_AB_128x128_custom_f(
  //  u8g2_Setup_st75256_jlx256128_f(
  //    &u8g2, U8G2_R0, u8g2_esp32_spi_byte_cb, u8g2_esp32_gpio_and_delay_cb);

  u8g2_InitDisplay(&u8g2);  // send library's init sequence to the display
  // u8g2_SetPowerSave(&u8g2, 0);  // wake up the display
}

it seems to rotate nicely with 0,0 as the offset

[MikeAtETI]

I've added a frame round it to check the frame rotate/flips ok, and that also looks good.

  u8g2_DrawStr(&u8g2, 10, 69, buffer);
        u8g2_DrawFrame(&u8g2, 0, 0, 128, 128);
        u8g2_SendBuffer(&u8g2);

It all looks good to us, thank you

[AlexBlows]

Thanks Mike for testing the beta release. @olikraus really appreciate you adding this new display. Whats the next step?

[olikraus]

Thanks for testing.

Next Steps... well, you can use the beta release and at some point in future, I will also create a regular release, which will then appear in Arduino IDE (this is not yet the case).

Is there some need for quickly having the update in Arduino IDE?

[AlexBlows]

We have approx 6 months of further development before we release our product. We can continue with the beta release and switch to the regular release when it becomes available (hopefully before then). We are coding with ESP-IDF & VSCode, so no need for a quick Arduino release on our behalf.

[olikraus]

The official release doesn't differ from the beta release. It just is the official download via Arduino IDE.