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Screen

The screen is used by all other functions and libraries.

Configure

Select the library corresponding to the size of the screen and the edition of the library.

#include "PDLS_EXT3_Advanced_Fast.h";
Legacy version 5
#include "PDLS_EXT3_Advanced_Fast_Small.h";

The pre-processor statement includes the screen libraries.

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Screen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09,
    boardRaspberryPiPico_RP2040,
    frameBuffer);

The constructor Screen_EPD_EXT3_Fast creates the screen object.

The required parameters are

The optional parameter is

  • The third line links to the frame-buffer if declared at build-time.

Screen model

The screen model starts with eScreen_EPD_EXT3_, contains the size and the type, both taken from the product number.

The product number of the panel is printed on the back of the screen, on the top line close to the QR-code.

Example

The screen with product number CE2271CS094 corresponds to a 2.71" panel with type 09. The last digit 4 is ignored.

- Size - Type -
CE2 271 CS 09 4
eScreen_EPD_EXT3_ 271 _ 09

The screen model for the constructor is eScreen_EPD_EXT3_271_09.

eScreen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09, boardRaspberryPiPico_RP2040);

Other specific cases for the constructor are listed below.

The product number of the screens with global update only includes a C after the size.

The screen model starts with eScreen_EPD_EXT3_ and mentions the size of the screen. Although the type of the screen can be omitted, it is recommended to include it.

Example

The product number of the screens with global update only includes a C after the size 271.

The screen with product number CE2271CS0E corresponds to a 2.71" panel with type 0E.

- Size - Type
CE2 271 CS 0E
eScreen_EPD_EXT3_ 271

The screen model for the constructor is eScreen_EPD_EXT3_271.

eScreen_EPD_EXT3 myScreen(eScreen_EPD_EXT3_271, boardRaspberryPiPico_RP2040);

A better solution is to include the type with eScreen_EPD_EXT3_271_0E.

eScreen_EPD_EXT3 myScreen(eScreen_EPD_EXT3_271_09, boardRaspberryPiPico_RP2040);

The product number of the screens with red colour update includes a J after the size.

The screens featuring red colour require the additional mention of Red.

The screen model starts with eScreen_EPD_EXT3_ and contains the size and the type, both taken from the product number, then _ and Red.

Example

The screen with product number CE2969JS08 corresponds to a 9.69" black-white-red panel with type 0B.

- Size - Type Red
CE2 969 JS 0B
eScreen_EPD_EXT3_ 969 _ 0B _Red

The screen model for the constructor is eScreen_EPD_EXT3_969_0B_Red.

eScreen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_969_0B_Red, boardRaspberryPiPico_RP2040);

The size of the 12.0" panel is coded as B98 and corresponds to 11.98".

The product number of the screens with embedded fast update includes a P after the size.

Screens with embedded fast update require the additional mention of Fast.

The screen model starts with eScreen_EPD_EXT3_ and contains the size and the type, both taken from the product number, then _ and Fast.

Example

The product number of the screens with embedded fast update includes a P after the size 271.

The screen with product number SE2271PS09 corresponds to a 2.71" panel with embedded fast update with type 09.

- Size - Type Fast
SE2 271 PS 09
eScreen_EPD_EXT3_ 271 _ 09 _Fast

The screen model for the constructor is eScreen_EPD_EXT3_271_09_Fast.

eScreen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09_Fast, boardRaspberryPiPico_RP2040);

The product number of the screens with wide temperature includes a K after the size.

Screens with wide temperature and embedded fast update require the additional mention of Wide.

The screen model starts with eScreen_EPD_EXT3_ and contains the size and the type, both taken from the product number, then _ and Wide.

The application note Manage temperatures discusses how to use the screens with wide temperature.

Example

The product number of the screens with touch includes a K after the size 271.

The screen with product number SE2271KS09 corresponds to a 2.71" panel with embedded fast update with type 09.

- Size - Type Fast
SE2 271 KS 09
eScreen_EPD_EXT3_ 271 _ 09 _Wide

The screen model for the constructor is eScreen_EPD_EXT3_271_09_Wide.

eScreen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09_Wide, boardRaspberryPiPico_RP2040);

The screens featuring touch require the additional mention of Touch.

The screen model starts with eScreen_EPD_EXT3_ and contains the size and the type, both taken from the product number, then _ and Touch.

Example

The product number of the screens with touch includes a T at the second position.

The screen with product number QT2370PS0C1 corresponds to a 3.70" touch-panel with type 0C.

- Size - Type Touch
QT2 370 PS 0C
eScreen_EPD_EXT3_ 370 _ 0C _Touch

The screen model for the constructor is eScreen_EPD_EXT3_370_0C_Touch.

eScreen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_370_0C_Touch, boardRaspberryPiPico_RP2040);

For more information about the screen model, please refer to the Model name explanation page.

Board configuration

A board configuration defines all the GPIOs connected to the EXT3 extension board.

The SPI and I²C ports set their respective pins.

There are three families of boards. The configuration file lists the recommended boards and includes other boards. Additional non-listed boards can easily be defined.

The recommended boards are:

Constant Board
boardFeatherNRF52840 Adafruit Feather
boardESP32DevKitC ​Espressif ESP32-DevKitC
boardRaspberryPiPico_RP2040 Raspberry Pi Pico with Arduino-Pico

Those recommended boards have been extensively tested. The Raspberry Pi Pico with Arduino-Pico is part of the the EPD Pico Kit (EPDK) .

Other boards are also available:

Constant Board
boardArduinoZero Arduino Zero or M0 Pro
boardFeatherNRF52832 Adafruit Feather
boardFeatherNRF52840 Adafruit Feather
boardFeatherRP2040 Adafruit Feather
boardParticlePhoton Particle Photon and RedBear Duo
boardRaspberryPiZeroB_RasPiArduino Raspberry Pi Zero and B
boardRaspberryPiZeroB_BCM2835 Raspberry Pi Zero and B
boardRaspberryPiZeroB_MRAA Raspberry Pi Zero and B
boardRaspberryPiPico_Arduino Raspberry Pi Pico with Arduino Core mbed
boardNucleo64 STM32 Nucleo
boardRaspberryPiPico_RP2040 Texas Instruments LaunchPad MSP430 and MSP432
boardCC1352 Texas Instruments LaunchPad and LPSTK CC1352R

Those boards are for reference only, as they may require specific SDK configurations.

To use another non-listed board,

  • Create a variable with the pins_t structure;
  • Set the pins of the connected GPIOs, or specify NOT_CONNECTED otherwise;
  • Mention this variable to the constructor.
Example
const pins_t myBoard =
{
    .panelBusy = 11, ///< EXT3 and EXT3-1 pin 3 Red
    .panelDC = 12, ///< EXT3 and EXT3-1 pin 4 Orange
    .panelReset = 13, ///< EXT3 and EXT3-1 pin 5 Yellow
    .flashCS = 18, ///< EXT3 and EXT3-1 pin 8 Violet
    .panelCS = 19, ///< EXT3 and EXT3-1 pin 9 Grey
    .panelCSS = 39, ///< EXT3 and EXT3-1 pin 12 Grey2
    .flashCSS = 38, ///< EXT3 and EXT3-1 pin 20 Black2
    .touchInt = NOT_CONNECTED, ///< EXT3-Touch pin 3 Red
    .touchReset = NOT_CONNECTED, ///< EXT3-Touch pin 4 Orange
    .panelPower = NOT_CONNECTED, ///< Optional power circuit 
    .cardCS = NOT_CONNECTED, ///< Separate SD-card board
    .cardDetect = NOT_CONNECTED, ///< Separate SD-card board
};

Screen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271, myBoard);

Frame-buffer

By default, the frame-buffer is created at run-time with the MCU internal SRAM.

The size of the frame-buffer corresponds to the number of pixels divided by 8 (8 pixels per byte) and multiplied by two (1 bit per colour, two colours or previous and next images).

Diagonal (inches) Width (pixels) Height (pixels) Frame-buffer (bytes)
1.54 152 152 5,776
2.13 104 212 5,512
2.66 152 296 11,248
2.71 176 264 11,616
2.87 128 296 9,472
3.70 240 416 24,960
4.17 400 300 30,000
4.37 176 480 21,120
5.81 256 720 46,080
7.41 480 800 96,000
9.69 672 960 161,280
11.98 768 960 184,320

However, the frame-buffer can be specified at build-time and passed on to the constructor as parameter.

uint8_t frameBuffer[frameSize_EPD_EXT3_271];
Screen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09, boardRaspberryPiPico_RP2040, frameBuffer);

The constant for the size of the frame-buffer starts with frameBuffer_EPD_EXT3_ and contains the size taken from the product number.

Diagonal (inches) Frame-buffer (bytes) Frame-buffer (constant)
1.54 5,776 frameBuffer_EPD_EXT3_154
2.13 5,512 frameBuffer_EPD_EXT3_213
2.66 11,248 frameBuffer_EPD_EXT3_266
2.71 11,616 frameBuffer_EPD_EXT3_271
2.87 9,472 frameBuffer_EPD_EXT3_287
3.70 24,960 frameBuffer_EPD_EXT3_370
4.17 30,000 frameBuffer_EPD_EXT3_417
4.37 21,120 frameBuffer_EPD_EXT3_437
5.81 46,080 frameBuffer_EPD_EXT3_581
7.41 96,000 frameBuffer_EPD_EXT3_741
9.69 161,280 frameBuffer_EPD_EXT3_969
11.98 184,320 frameBuffer_EPD_EXT3_B98

Specifying the frame-buffer at build-time is required for the cases listed below.

For MCUs where the memory location is managed at build-time such as FRAM-based MSP430FR5994, use instead

uint8_t frameBuffer[frameSize_EPD_EXT3_271] PLACE_IN_FRAM;
Screen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09, boardLaunchPad, frameBuffer);

The PLACE_IN_FRAM macro tells the compiler to locate the frame-buffer in upper-FRAM.

For MCUs which manage external memory such as ESP32 with PSRAM or pseudo-static RAM, use instead

uint8_t * frameBuffer = (uint8_t *) ps_malloc(frameSize_EPD_EXT3_271);
Screen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09, boardESP32DevKitC, frameBuffer);

The ps_malloc() allocator tells the compiler to locate the frame-buffer on the PSRAM.

Use

myScreen.begin();

begin() initialises the screen, including the required GPIOs, and the SPI and I²C ports.

Up to three different update modes are available for the panels: global update for all the monochrome and colour screens, fast update for selected monochrome screens, and partial update for screens with touch.

myScreen.gText(4, 4, myScreen.whoAmI());
myScreen.flush();

whoAmI() returns the name of the screen.

gText() prints text on the screen.

flush() uploads the frame-buffer to the screen and performs a global update of the panel.

myScreen.gText(4, 4, myScreen.whoAmI());
myScreen.flushFast();

whoAmI() returns the name of the screen.

gText() prints text on the screen.

flushFast() uploads the frame-buffer to the screen and performs a fast update of the panel.

When global update is not available, flush() redirects to flushFast().

The application note provides the procedure to Optimise update modes.

Warning

The partial update mode is deprecated, except for the screens with touch. Use fast update instead.

myScreen.gText(4, 4, myScreen.whoAmI());
myScreen.flushPartial();

whoAmI() returns the name of the screen.

gText() prints text on the screen.

The coordinates of the modified window are updated automatically when drawing text and graphics.

flushPartial() uploads the modified window from the frame-buffer to the screen, and performs a partial update of the panel.

Note

For small screens, partial update may not be faster than fast update.

Legacy version 5

Legacy version 5 requires beginPartial() to start partial mode and reset the coordinates of the window.

myScreen.beginPartial();
myScreen.gText(4, 4, myScreen.whoAmI());
myScreen.flushPartial();

beginPartial() starts the partial mode and resets the coordinates of the window.

The application note provides the procedure to Optimise update modes.

The parametric update is recommended for screens with wide temperature range.

myScreen.gText(4, 4, myScreen.whoAmI());
myScreen.setTemperatureC(25);
uint8_t mode = myScreen.flushMode(UPDATE_FAST);

whoAmI() returns the name of the screen.

gText() prints text on the screen.

setTemperatureC() sets the temperature in degrees Celsius, with default value 25 °C. For temperature in degrees Fahrenheit, use setTemperatureF() with default value 77 °F.

flushMode() checks the compatibility of the update mode with the temperature, performs the refresh when possible and returns the mode used.

If the temperature is out of range, no refresh is carried out and the function returns UPDATE_NONE.

The application note provides the procedure to Manage temperature.

The functions are grouped in six categories.

Example

This is the core of the code from the example WhoAmI.ino.

// Screen
#include "PDLS_EXT3_Advanced_Fast_Small.h";

// SDK
#include "hV_HAL_Peripherals.h"

// Configuration
#include "hV_Configuration.h"

// Set parameters
#define DISPLAY_WHOAMI 1

// Include application, user and local libraries
#include "hV_Utilities.h"

// Define variables and constants
Screen_EPD_EXT3_Fast myScreen(eScreen_EPD_EXT3_271_09, boardRaspberryPiPico_RP2040);

uint8_t fontSans;

#if (DISPLAY_WHOAMI == 1)

void displayWhoAmI()
{
    myScreen.selectFont(fontSans);
    myScreen.setOrientation(myOrientation);

    myScreen.gText(4, 4, myScreen.WhoAmI());

    // Global update
    myScreen.flush();
}

#endif // DISPLAY_WHOAMI

// Add setup code
void setup()
{
    hV_HAL_begin();

    hV_HAL_Debug_begin(115200);
    hV_HAL_delayMilliseconds(500);
    hV_HAL_crlf();
    hV_HAL_printf("=== " __FILE__);
    hV_HAL_crlf();
    hV_HAL_printf("=== " __DATE__ " " __TIME__);
    hV_HAL_crlf();

    // initialise screen
    hV_HAL_printf("begin... ");
    myScreen.begin();
    hV_HAL_printf("done");
    hV_HAL_crlf();

    // Add fonts from header files
    fontSans = myScreen.addFont(Font_DejaVuSans16);
    fontSans -= (fontSans > 0) ? 1 : 0;

    // Example
#if (DISPLAY_WHOAMI == 1)

    hV_HAL_printf("DISPLAY_WHOAMI... ");
    myScreen.clear();
    displayWhoAmI();
    hV_HAL_printf("done");
    hV_HAL_crlf();

    wait(4);

#endif // DISPLAY_WHOAMI

    hV_HAL_printf("===");
    hV_HAL_crlf();
    hV_HAL_exit(0);
}

// Add loop code
void loop()
{
    hV_HAL_delayMilliseconds(1000);
}