diff --git a/ImageDemo/CMakeLists.txt b/ImageDemo/CMakeLists.txt
new file mode 100644
index 0000000..2aa16fe
--- /dev/null
+++ b/ImageDemo/CMakeLists.txt
@@ -0,0 +1,8 @@
+# The following lines of boilerplate have to be in your project's CMakeLists
+# in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.5)
+
+set(EXTRA_COMPONENT_DIRS ../components/ssd1306)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(ssd1306)
diff --git a/ImageDemo/README.md b/ImageDemo/README.md
new file mode 100644
index 0000000..d771e46
--- /dev/null
+++ b/ImageDemo/README.md
@@ -0,0 +1,8 @@
+# ImageDemo for SSD1306
+
+![ImageDemo-1](https://user-images.githubusercontent.com/6020549/165235302-6909f7c4-78e2-4c9d-8cb3-81eb9c920534.JPG)
+![ImageDemo-2](https://user-images.githubusercontent.com/6020549/165235310-88430dc3-5bed-4190-99e4-fe268c449218.JPG)
+
+
+I borrowed the BIT MAP data from [here](https://www.mischianti.org/2021/07/14/ssd1306-oled-display-draw-images-splash-and-animations-2/).
+
diff --git a/ImageDemo/main/CMakeLists.txt b/ImageDemo/main/CMakeLists.txt
new file mode 100644
index 0000000..647a294
--- /dev/null
+++ b/ImageDemo/main/CMakeLists.txt
@@ -0,0 +1,4 @@
+set(COMPONENT_SRCS "main.c")
+set(COMPONENT_ADD_INCLUDEDIRS "")
+
+register_component()
diff --git a/ImageDemo/main/_ b/ImageDemo/main/_
new file mode 100644
index 0000000..e60068b
--- /dev/null
+++ b/ImageDemo/main/_
@@ -0,0 +1,211 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+
+#include "ssd1306.h"
+#include "font8x8_basic.h"
+
+/*
+ You have to set this config value with menuconfig
+ CONFIG_INTERFACE
+
+ for i2c
+ CONFIG_MODEL
+ CONFIG_SDA_GPIO
+ CONFIG_SCL_GPIO
+ CONFIG_RESET_GPIO
+
+ for SPI
+ CONFIG_CS_GPIO
+ CONFIG_DC_GPIO
+ CONFIG_RESET_GPIO
+*/
+
+#define TAG "SSD1306"
+
+// https://www.mischianti.org/2021/07/14/ssd1306-oled-display-draw-images-splash-and-animations-2/
+uint8_t batman[] = {
+		0b11111111, 0b11111111, 0b11111111, 0b11111111,
+		0b11111111, 0b10011111, 0b11111001, 0b11111111,
+		0b11111110, 0b00111110, 0b01111100, 0b01111111,
+		0b11111000, 0b00111100, 0b00111100, 0b00011111,
+		0b11110000, 0b00011100, 0b00111000, 0b00001111,
+		0b11110000, 0b00000000, 0b00000000, 0b00001111,
+		0b11100000, 0b00000000, 0b00000000, 0b00000111,
+		0b11100000, 0b00000000, 0b00000000, 0b00000111,
+		0b11110000, 0b00000000, 0b00000000, 0b00001111,
+		0b11110000, 0b11000100, 0b00100011, 0b00001111,
+		0b11111001, 0b11111110, 0b01111111, 0b10011111,
+		0b11111100, 0b11111110, 0b01111111, 0b00111111,
+		0b11111111, 0b11111111, 0b11111111, 0b11111111
+};
+
+// https://www.mischianti.org/2021/07/14/ssd1306-oled-display-draw-images-splash-and-animations-2/
+uint8_t logoMischianti [1024] = {
+		// 'logoBN128x64, 128x64px
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xe0, 0x07, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xe0, 0x07, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf0, 0x07, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf3, 0xcf, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe0, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xc0, 0x7f, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe7, 0xc0, 0x7f, 0xe7, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xe0, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x01, 0xf8, 0x0f, 0xff, 0xff, 0xf0, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x03, 0xe0, 0x03, 0xff, 0xff, 0xc0, 0x03, 0xc0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x80, 0x00, 0xff, 0xff, 0x00, 0x41, 0xe0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x00, 0x00, 0x7f, 0xfe, 0x00, 0xe0, 0xf0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x0f, 0xf0, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x07, 0xe0, 0x00, 0xe0, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x7f, 0xf0, 0x03, 0xe0, 0x00, 0xe0, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x7f, 0xf0, 0x03, 0xc0, 0x1f, 0xff, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x7f, 0xf0, 0x03, 0xe0, 0x1f, 0xff, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x07, 0xe0, 0x00, 0x60, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x0f, 0xf0, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x00, 0x00, 0x7c, 0x3e, 0x00, 0xe0, 0xf0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x80, 0x00, 0xf8, 0x1f, 0x00, 0x61, 0xe0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x03, 0xc0, 0x03, 0xe0, 0x07, 0xc0, 0x03, 0xc0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x01, 0xf8, 0x0f, 0xc0, 0x03, 0xf0, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x38, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3c, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe0, 0x07, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf0, 0x0f, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfc, 0x3f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7f, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x08, 0x10, 0x00, 0x00, 0x80, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x46, 0x63, 0x31, 0x90, 0xff, 0x13, 0xc3, 0x8b, 0x91, 0xe5, 0xdc, 0x80, 0xf3, 0xbf, 0x00,
+		0x00, 0x66, 0x73, 0x39, 0x90, 0xcd, 0x92, 0x24, 0x4c, 0x92, 0x26, 0x48, 0x81, 0x13, 0x27, 0x00,
+		0x00, 0x2e, 0x57, 0x2b, 0x90, 0x88, 0x93, 0x04, 0x08, 0xd0, 0x24, 0x68, 0x81, 0x1a, 0x23, 0x00,
+		0x00, 0x2a, 0xd5, 0x6a, 0xb0, 0x88, 0x91, 0xcc, 0x08, 0xd3, 0xe4, 0x68, 0x83, 0x1a, 0x63, 0x00,
+		0x00, 0x2b, 0x95, 0xca, 0xe0, 0x88, 0x90, 0x64, 0x08, 0xd2, 0x24, 0x68, 0x81, 0x1a, 0x63, 0x00,
+		0x00, 0x39, 0x9c, 0xce, 0x60, 0x88, 0x96, 0x24, 0x48, 0xd6, 0x64, 0x68, 0x81, 0x12, 0x27, 0x00,
+		0x00, 0x11, 0x88, 0xc4, 0x6c, 0x88, 0x93, 0xc3, 0x88, 0xd3, 0xb4, 0x6e, 0x98, 0xf2, 0x3f, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x22, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3c, 0x00
+};
+
+void app_main(void)
+{
+	SSD1306_t dev;
+
+#if CONFIG_I2C_INTERFACE
+	ESP_LOGI(TAG, "INTERFACE is i2c");
+	ESP_LOGI(TAG, "CONFIG_SDA_GPIO=%d",CONFIG_SDA_GPIO);
+	ESP_LOGI(TAG, "CONFIG_SCL_GPIO=%d",CONFIG_SCL_GPIO);
+	ESP_LOGI(TAG, "CONFIG_RESET_GPIO=%d",CONFIG_RESET_GPIO);
+	i2c_master_init(&dev, CONFIG_SDA_GPIO, CONFIG_SCL_GPIO, CONFIG_RESET_GPIO);
+#endif // CONFIG_I2C_INTERFACE
+
+#if CONFIG_SPI_INTERFACE
+	ESP_LOGI(TAG, "INTERFACE is SPI");
+	ESP_LOGI(TAG, "CONFIG_MOSI_GPIO=%d",CONFIG_MOSI_GPIO);
+	ESP_LOGI(TAG, "CONFIG_SCLK_GPIO=%d",CONFIG_SCLK_GPIO);
+	ESP_LOGI(TAG, "CONFIG_CS_GPIO=%d",CONFIG_CS_GPIO);
+	ESP_LOGI(TAG, "CONFIG_DC_GPIO=%d",CONFIG_DC_GPIO);
+	ESP_LOGI(TAG, "CONFIG_RESET_GPIO=%d",CONFIG_RESET_GPIO);
+	spi_master_init(&dev, CONFIG_MOSI_GPIO, CONFIG_SCLK_GPIO, CONFIG_CS_GPIO, CONFIG_DC_GPIO, CONFIG_RESET_GPIO);
+#endif // CONFIG_SPI_INTERFACE
+
+#if CONFIG_FLIP
+	dev._flip = true;
+	ESP_LOGW(TAG, "Flip upside down");
+#endif
+
+#if CONFIG_SSD1306_128x64
+	ESP_LOGI(TAG, "Panel is 128x64");
+	ssd1306_init(&dev, 128, 64);
+#endif // CONFIG_SSD1306_128x64
+#if CONFIG_SSD1306_128x32
+	ESP_LOGI(TAG, "Panel is 128x32");
+	ssd1306_init(&dev, 128, 32);
+#endif // CONFIG_SSD1306_128x32
+
+	ssd1306_clear_screen(&dev, false);
+
+#if 0
+	// for test code
+	int srcBits = 7;
+	int dstBits = 0;
+	for (int i=0;i<8;i++) {
+		uint8_t dst = 0;
+		dst = ssd1306_copy_bit(0xf0, srcBits, dst, dstBits);
+		ESP_LOGI(TAG, "dst=%02x", dst);
+		srcBits--;
+		dstBits++;
+	}
+	srcBits = 7;
+	dstBits = 0;
+	for (int i=0;i<8;i++) {
+		uint8_t dst = 0;
+		dst = ssd1306_copy_bit(0x0f, srcBits, dst, dstBits);
+		ESP_LOGI(TAG, "dst=%02x", dst);
+		srcBits--;
+		dstBits++;
+	}
+#endif
+
+	while(1) {
+	ssd1306_contrast(&dev, 0xff);
+#if CONFIG_SSD1306_128x64
+	ssd1306_display_text(&dev, 0, "SSD1306 128x64", 14, false);
+#endif // CONFIG_SSD1306_128x64
+
+#if CONFIG_SSD1306_128x32
+	ssd1306_display_text(&dev, 0, "SSD1306 128x32", 14, false);
+#endif // CONFIG_SSD1306_128x32
+	ssd1306_display_text(&dev, 1, "BATMAN", 6, false);
+
+	int bitmapWidth = 4*8;
+	int width = ssd1306_get_width(&dev);
+	int xpos = width / 2; // center of width
+	xpos = xpos - bitmapWidth/2; 
+	int ypos = 16;
+	ESP_LOGI(TAG, "width=%d xpos=%d", width, xpos);
+	ssd1306_bitmaps(&dev, xpos, ypos, batman, 4, 12);
+	vTaskDelay(3000 / portTICK_PERIOD_MS);
+
+	for(int i=0;i<128;i++) {
+		ssd1306_rotate(&dev, SCROLL_RIGHT, 2, 3, 0);
+	}
+	vTaskDelay(2000 / portTICK_PERIOD_MS);
+
+#if CONFIG_SSD1306_128x64
+	ssd1306_clear_screen(&dev, false);
+	ssd1306_bitmaps(&dev, 0, 0, logoMischianti, 16, 64);
+	vTaskDelay(2000 / portTICK_PERIOD_MS);
+
+	for(int i=0;i<64;i++) {
+		ssd1306_rotate(&dev, SCROLL_UP, 0, 127, 0);
+	}
+	vTaskDelay(2000 / portTICK_PERIOD_MS);
+#endif
+	}
+}
diff --git a/ImageDemo/main/component.mk b/ImageDemo/main/component.mk
new file mode 100644
index 0000000..61f8990
--- /dev/null
+++ b/ImageDemo/main/component.mk
@@ -0,0 +1,8 @@
+#
+# Main component makefile.
+#
+# This Makefile can be left empty. By default, it will take the sources in the 
+# src/ directory, compile them and link them into lib(subdirectory_name).a 
+# in the build directory. This behaviour is entirely configurable,
+# please read the ESP-IDF documents if you need to do this.
+#
diff --git a/ImageDemo/main/main.c b/ImageDemo/main/main.c
new file mode 100644
index 0000000..8be377d
--- /dev/null
+++ b/ImageDemo/main/main.c
@@ -0,0 +1,211 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+
+#include "ssd1306.h"
+#include "font8x8_basic.h"
+
+/*
+ You have to set this config value with menuconfig
+ CONFIG_INTERFACE
+
+ for i2c
+ CONFIG_MODEL
+ CONFIG_SDA_GPIO
+ CONFIG_SCL_GPIO
+ CONFIG_RESET_GPIO
+
+ for SPI
+ CONFIG_CS_GPIO
+ CONFIG_DC_GPIO
+ CONFIG_RESET_GPIO
+*/
+
+#define TAG "SSD1306"
+
+// https://www.mischianti.org/2021/07/14/ssd1306-oled-display-draw-images-splash-and-animations-2/
+uint8_t batman[] = {
+		0b11111111, 0b11111111, 0b11111111, 0b11111111,
+		0b11111111, 0b10011111, 0b11111001, 0b11111111,
+		0b11111110, 0b00111110, 0b01111100, 0b01111111,
+		0b11111000, 0b00111100, 0b00111100, 0b00011111,
+		0b11110000, 0b00011100, 0b00111000, 0b00001111,
+		0b11110000, 0b00000000, 0b00000000, 0b00001111,
+		0b11100000, 0b00000000, 0b00000000, 0b00000111,
+		0b11100000, 0b00000000, 0b00000000, 0b00000111,
+		0b11110000, 0b00000000, 0b00000000, 0b00001111,
+		0b11110000, 0b11000100, 0b00100011, 0b00001111,
+		0b11111001, 0b11111110, 0b01111111, 0b10011111,
+		0b11111100, 0b11111110, 0b01111111, 0b00111111,
+		0b11111111, 0b11111111, 0b11111111, 0b11111111
+};
+
+// https://www.mischianti.org/2021/07/14/ssd1306-oled-display-draw-images-splash-and-animations-2/
+uint8_t logoMischianti [1024] = {
+		// 'logoBN128x64, 128x64px
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xe0, 0x07, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xe0, 0x07, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf0, 0x07, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf3, 0xcf, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xff, 0xff, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe0, 0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xc0, 0x7f, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe7, 0xc0, 0x7f, 0xe7, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xe0, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x01, 0xf8, 0x0f, 0xff, 0xff, 0xf0, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x03, 0xe0, 0x03, 0xff, 0xff, 0xc0, 0x03, 0xc0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x80, 0x00, 0xff, 0xff, 0x00, 0x41, 0xe0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x00, 0x00, 0x7f, 0xfe, 0x00, 0xe0, 0xf0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x0f, 0xf0, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x07, 0xe0, 0x00, 0xe0, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x7f, 0xf0, 0x03, 0xe0, 0x00, 0xe0, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x7f, 0xf0, 0x03, 0xc0, 0x1f, 0xff, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x7f, 0xf0, 0x03, 0xe0, 0x1f, 0xff, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x07, 0xe0, 0x00, 0x60, 0x38, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x0f, 0xf0, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x0e, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0xe0, 0x70, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x00, 0x00, 0x7c, 0x3e, 0x00, 0xe0, 0xf0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x07, 0x80, 0x00, 0xf8, 0x1f, 0x00, 0x61, 0xe0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x03, 0xc0, 0x03, 0xe0, 0x07, 0xc0, 0x03, 0xc0, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x01, 0xf8, 0x0f, 0xc0, 0x03, 0xf0, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xff, 0xff, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0xff, 0xff, 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x38, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3c, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1c, 0x00, 0x00, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xff, 0xff, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xff, 0xff, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, 0xff, 0xff, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe0, 0x07, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0xf0, 0x0f, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfc, 0x3f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7f, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1f, 0xf8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0xf0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x08, 0x10, 0x00, 0x00, 0x80, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x46, 0x63, 0x31, 0x90, 0xff, 0x13, 0xc3, 0x8b, 0x91, 0xe5, 0xdc, 0x80, 0xf3, 0xbf, 0x00,
+		0x00, 0x66, 0x73, 0x39, 0x90, 0xcd, 0x92, 0x24, 0x4c, 0x92, 0x26, 0x48, 0x81, 0x13, 0x27, 0x00,
+		0x00, 0x2e, 0x57, 0x2b, 0x90, 0x88, 0x93, 0x04, 0x08, 0xd0, 0x24, 0x68, 0x81, 0x1a, 0x23, 0x00,
+		0x00, 0x2a, 0xd5, 0x6a, 0xb0, 0x88, 0x91, 0xcc, 0x08, 0xd3, 0xe4, 0x68, 0x83, 0x1a, 0x63, 0x00,
+		0x00, 0x2b, 0x95, 0xca, 0xe0, 0x88, 0x90, 0x64, 0x08, 0xd2, 0x24, 0x68, 0x81, 0x1a, 0x63, 0x00,
+		0x00, 0x39, 0x9c, 0xce, 0x60, 0x88, 0x96, 0x24, 0x48, 0xd6, 0x64, 0x68, 0x81, 0x12, 0x27, 0x00,
+		0x00, 0x11, 0x88, 0xc4, 0x6c, 0x88, 0x93, 0xc3, 0x88, 0xd3, 0xb4, 0x6e, 0x98, 0xf2, 0x3f, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x22, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3c, 0x00
+};
+
+void app_main(void)
+{
+	SSD1306_t dev;
+
+#if CONFIG_I2C_INTERFACE
+	ESP_LOGI(TAG, "INTERFACE is i2c");
+	ESP_LOGI(TAG, "CONFIG_SDA_GPIO=%d",CONFIG_SDA_GPIO);
+	ESP_LOGI(TAG, "CONFIG_SCL_GPIO=%d",CONFIG_SCL_GPIO);
+	ESP_LOGI(TAG, "CONFIG_RESET_GPIO=%d",CONFIG_RESET_GPIO);
+	i2c_master_init(&dev, CONFIG_SDA_GPIO, CONFIG_SCL_GPIO, CONFIG_RESET_GPIO);
+#endif // CONFIG_I2C_INTERFACE
+
+#if CONFIG_SPI_INTERFACE
+	ESP_LOGI(TAG, "INTERFACE is SPI");
+	ESP_LOGI(TAG, "CONFIG_MOSI_GPIO=%d",CONFIG_MOSI_GPIO);
+	ESP_LOGI(TAG, "CONFIG_SCLK_GPIO=%d",CONFIG_SCLK_GPIO);
+	ESP_LOGI(TAG, "CONFIG_CS_GPIO=%d",CONFIG_CS_GPIO);
+	ESP_LOGI(TAG, "CONFIG_DC_GPIO=%d",CONFIG_DC_GPIO);
+	ESP_LOGI(TAG, "CONFIG_RESET_GPIO=%d",CONFIG_RESET_GPIO);
+	spi_master_init(&dev, CONFIG_MOSI_GPIO, CONFIG_SCLK_GPIO, CONFIG_CS_GPIO, CONFIG_DC_GPIO, CONFIG_RESET_GPIO);
+#endif // CONFIG_SPI_INTERFACE
+
+#if CONFIG_FLIP
+	dev._flip = true;
+	ESP_LOGW(TAG, "Flip upside down");
+#endif
+
+#if CONFIG_SSD1306_128x64
+	ESP_LOGI(TAG, "Panel is 128x64");
+	ssd1306_init(&dev, 128, 64);
+#endif // CONFIG_SSD1306_128x64
+#if CONFIG_SSD1306_128x32
+	ESP_LOGI(TAG, "Panel is 128x32");
+	ssd1306_init(&dev, 128, 32);
+#endif // CONFIG_SSD1306_128x32
+
+	ssd1306_contrast(&dev, 0xff);
+
+#if 0
+	// for test code
+	int srcBits = 7;
+	int dstBits = 0;
+	for (int i=0;i<8;i++) {
+		uint8_t dst = 0;
+		dst = ssd1306_copy_bit(0xf0, srcBits, dst, dstBits);
+		ESP_LOGI(TAG, "dst=%02x", dst);
+		srcBits--;
+		dstBits++;
+	}
+	srcBits = 7;
+	dstBits = 0;
+	for (int i=0;i<8;i++) {
+		uint8_t dst = 0;
+		dst = ssd1306_copy_bit(0x0f, srcBits, dst, dstBits);
+		ESP_LOGI(TAG, "dst=%02x", dst);
+		srcBits--;
+		dstBits++;
+	}
+#endif
+
+	while(1) {
+		ssd1306_clear_screen(&dev, false);
+#if CONFIG_SSD1306_128x64
+		ssd1306_display_text(&dev, 0, "SSD1306 128x64", 14, false);
+#endif // CONFIG_SSD1306_128x64
+
+#if CONFIG_SSD1306_128x32
+		ssd1306_display_text(&dev, 0, "SSD1306 128x32", 14, false);
+#endif // CONFIG_SSD1306_128x32
+		ssd1306_display_text(&dev, 1, "BATMAN", 6, false);
+
+		int bitmapWidth = 4*8;
+		int width = ssd1306_get_width(&dev);
+		int xpos = width / 2; // center of width
+		xpos = xpos - bitmapWidth/2; 
+		int ypos = 16;
+		ESP_LOGD(TAG, "width=%d xpos=%d", width, xpos);
+		ssd1306_bitmaps(&dev, xpos, ypos, batman, 4, 12);
+		vTaskDelay(3000 / portTICK_PERIOD_MS);
+
+		for(int i=0;i<128;i++) {
+			ssd1306_rotate(&dev, SCROLL_RIGHT, 2, 3, 0);
+		}
+		vTaskDelay(2000 / portTICK_PERIOD_MS);
+
+#if CONFIG_SSD1306_128x64
+		ssd1306_clear_screen(&dev, false);
+		ssd1306_bitmaps(&dev, 0, 0, logoMischianti, 16, 64);
+		vTaskDelay(2000 / portTICK_PERIOD_MS);
+
+		for(int i=0;i<64;i++) {
+			ssd1306_rotate(&dev, SCROLL_UP, 0, 127, 0);
+		}
+		vTaskDelay(2000 / portTICK_PERIOD_MS);
+#endif
+	}
+}