Oak

E-Ink hello world

e-ink e-paper waveshare display e-paper version 1 medium

Display simple string on E-Ink with increasing counter

Before starting

Dependancies

waveshare

Details

Waveshare E-Ink version

Check the E-Ink display module for the version number. Here, version 1 is used and the number is not marked on the module.

WaveShare 1.54 inch module

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 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.h"
#include "epdpaint.h"

#define COLORED 0
#define UNCOLORED 1

unsigned char image[1024];
Paint paint(image, 0, 0);
Epd epd;
int count = 0;
char count_string[] = {'0', '0', '0', '\0'};

void setup() {
  SerialUSB.begin(9600);

  SerialUSB.print("e-Paper init ");
  if (epd.Init(lut_full_update) != 0) {
    SerialUSB.print("e-Paper init failed");
    return;
  }
}

void loop() {
  sprintf(count_string, "%d", ++count);
  SerialUSB.println(count_string);

  epd.ClearFrameMemory(0xFF);  // bit set = white, bit reset = black
  epd.DisplayFrame();
  epd.ClearFrameMemory(0xFF);  // bit set = white, bit reset = black
  epd.DisplayFrame();

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

  paint.Clear(COLORED);
  paint.DrawStringAt(10, 4, "hello", &Font24, UNCOLORED);
  paint.DrawStringAt(10, 30, count_string, &Font24, UNCOLORED);
  epd.SetFrameMemory(paint.GetImage(),
    80, 72, paint.GetWidth(), paint.GetHeight());
  epd.DisplayFrame();

  delay(1000);
  epd.Sleep();
}

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