Oak | E-Ink hello world with V2.1

E-Ink hello world with V2.1

e-ink e-paper waveshare display e-paper version 2.1 medium

Display demo sample code with V2.1 E-Ink hardware version

Before starting

Dependancies

waveshare

Details

Waveshare E-Ink version

Check the E-Ink display module for the version number. Here, version 2.1 is used and the number is marked on the module.

WaveShare 1.54 inch module Version 2.1

SPI

The 4 non-SPI pins are defined in epdif.h file:

#define RST_PIN 8
#define DC_PIN 9
#define CS_PIN 10
#define BUSY_PIN 7

The SPI pins for Arduino Zero / SAMD21G are defined as following:

SAMD21G Pin	I/O Pin	SERCOM-ALT	Name
`19`	`PB10`	`SERCOM4/PAD[2]`	COPI
`20`	`PB11`	`SERCOM4/PAD[3]`	SCK

Pins in schematic

Schematic label	Arduino Zero pin name	SAMD21G pin name
EINK_BUSY	D7	PA21
EINK_RST	D8	PA06
EINK_DC	D9	PA07
EINK_CS	D10	PA18
COPI	ICSP_COPI	PB10
CLK	ICSP_SCK	PB11
CIPO	ICSP_CIPO	PA12

Steps

Plug in the Oak PCB with the E-Ink to the computer
(Option A) Ensure the PCB can be detected with ls -al /dev/cu.usbmodem and arduino-cli board list. Run make to compile and upload the code to the board.
(Option B) Ensure the board can be detected with Arduino IDE. Compile and upload the code to the board.
Start the serial monitor to view the console logs

Serial console

Serial output from the firmware.

Code

Download code

#include <SPI.h>
#include "epd1in54_V2.h"
#include "epdpaint.h"

Epd epd;
unsigned char image[1024];
Paint paint(image, 0, 0);

#define COLORED     0
#define UNCOLORED   1

int count = 0;
char count_string[] = {'0', '0', '0', '\0'};

void setup() {
  SerialUSB.begin(9600);
  SerialUSB.println("e-Paper init");
  initEink();
  delay(1000);
}

void loop() {
  displayOnEink();
  delay(2000);
}

bool initEink() {
  epd.LDirInit();
  epd.Clear();

  return true;
}

void displayOnEink() {
  sprintf(count_string, "%d", ++count);

  paint.SetWidth(200);
  paint.SetHeight(24);
  paint.SetRotate(ROTATE_0);

  paint.Clear(COLORED);
  paint.DrawStringAt(10, 4, "Lat Long!", &Font16, UNCOLORED);
  epd.SetFrameMemory(
      paint.GetImage(), 0, 10, paint.GetWidth(), paint.GetHeight());

  paint.Clear(UNCOLORED);
  paint.DrawStringAt(10, 4, "at ", &Font16, COLORED);
  paint.DrawStringAt(40, 4, "00:00", &Font16, COLORED);
  epd.SetFrameMemory(
      paint.GetImage(), 0, 30, paint.GetWidth(), paint.GetHeight());

  paint.SetWidth(50);
  paint.SetHeight(120);
  paint.SetRotate(ROTATE_270);

  paint.Clear(COLORED);
  paint.DrawStringAt(12, 10, count_string, &Font16, UNCOLORED);
  paint.DrawStringAt(12, 32, count_string, &Font16, UNCOLORED);
  epd.SetFrameMemory(
      paint.GetImage(), 80, 72, paint.GetWidth(), paint.GetHeight());

  epd.DisplayFrame();
  SerialUSB.println("e-Paper print " + String(count_string));
}

Makefile

BOARD?=hutscape:samd:oak
PORT := $(shell ls /dev/cu.usbmodem*)
BUILD=build

.PHONY: default lint all flash clean

default: all flash clean

all:
	arduino-cli compile --fqbn $(BOARD) --output-dir $(BUILD) ./

flash:
	arduino-cli upload -p $(PORT) --fqbn $(BOARD) --input-dir $(BUILD) --verbose

clean:
	rm -r build

References

Arduino Waveshare E-paper 1in54 version 2