diff --git a/main/CMakeLists.txt b/main/CMakeLists.txt
index c7a6e20..72bdf8d 100644
--- a/main/CMakeLists.txt
+++ b/main/CMakeLists.txt
@@ -1,4 +1,4 @@
-set(COMPONENT_SRCS "hello_world_main.c" "nokia.c")
+set(COMPONENT_SRCS "app_main.c" "nokia.c" "knob.c" "gui.c")
 set(COMPONENT_ADD_INCLUDEDIRS "")
 
 register_component()
diff --git a/main/app_main.c b/main/app_main.c
new file mode 100644
index 0000000..254137b
--- /dev/null
+++ b/main/app_main.c
@@ -0,0 +1,40 @@
+/* Hello World Example
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+*/
+#include <stdio.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_system.h"
+#include "esp_spi_flash.h"
+#include "nokia.h"
+#include "knob.h"
+#include "gui.h"
+
+
+void __attribute__((noreturn)) app_main()
+{
+    printf("Hello world!\n");
+
+    gpio_config_t output = {
+        .pin_bit_mask = (1<<22),
+        .mode = GPIO_MODE_OUTPUT
+    };
+    gpio_config(&output);
+
+
+    gui_init();
+
+    knob_init();
+
+    bool level = 0;
+    while (1) {
+        vTaskDelay(pdMS_TO_TICKS(1000));
+        gpio_set_level(22, level);
+        level ^= 1;
+    }
+}
diff --git a/main/gui.c b/main/gui.c
new file mode 100644
index 0000000..ae86fe6
--- /dev/null
+++ b/main/gui.c
@@ -0,0 +1,59 @@
+#include "gui.h"
+#include "nokia.h"
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+
+static void gui_thread(void *arg);
+
+TaskHandle_t hGuiThread = NULL;
+
+void gui_init() {
+    printf("GUI init\n");
+    LCD_setup();
+
+    LCD_clearDisplay(0);
+    LCD_setStr("Hello World", 0, 0, 1);
+    LCD_updateDisplay();
+
+    int rv = xTaskCreate(gui_thread, "gui", 4096, NULL, 3, &hGuiThread);
+    assert (rv == pdPASS);
+}
+
+static void __attribute__((noreturn)) gui_thread(void *arg) {
+    uint32_t pos = 20;
+#define NMAX 60
+    while (1) {
+        uint32_t value;
+        xTaskNotifyWait(0, ULONG_MAX, &value, portMAX_DELAY);
+        printf("Knob event 0x%02x  ", value);
+
+        switch (value) {
+            case 0b100:
+                printf("PUSH |");
+                break;
+
+            case 0b010:
+                printf("BACK |");
+                if (pos == 0) {
+                    pos = NMAX;
+                } else {
+                    pos--;
+                }
+                break;
+
+            case 0b001:
+                printf("FWD  |");
+                if (pos == NMAX) {
+                    pos = 0;
+                } else {
+                    pos += 1;
+                }
+                break;
+        }
+
+        for (int i=0; i<pos; i++) {
+            printf(" ");
+        }
+        printf("#\n");
+    }
+}
diff --git a/main/gui.h b/main/gui.h
new file mode 100644
index 0000000..b55c989
--- /dev/null
+++ b/main/gui.h
@@ -0,0 +1,10 @@
+#ifndef GUI_H
+#define GUI_H
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+
+extern TaskHandle_t hGuiThread;
+
+void gui_init();
+
+#endif //GUI_H
diff --git a/main/hello_world_main.c b/main/hello_world_main.c
deleted file mode 100644
index a6afae8..0000000
--- a/main/hello_world_main.c
+++ /dev/null
@@ -1,54 +0,0 @@
-/* Hello World Example
-
-   This example code is in the Public Domain (or CC0 licensed, at your option.)
-
-   Unless required by applicable law or agreed to in writing, this
-   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
-   CONDITIONS OF ANY KIND, either express or implied.
-*/
-#include <stdio.h>
-#include "freertos/FreeRTOS.h"
-#include "freertos/task.h"
-#include "esp_system.h"
-#include "esp_spi_flash.h"
-#include "nokia.h"
-
-
-void app_main()
-{
-    printf("Hello world!\n");
-
-    /* Print chip information */
-    esp_chip_info_t chip_info;
-    esp_chip_info(&chip_info);
-    printf("This is ESP32 chip with %d CPU cores, WiFi%s%s, ",
-            chip_info.cores,
-            (chip_info.features & CHIP_FEATURE_BT) ? "/BT" : "",
-            (chip_info.features & CHIP_FEATURE_BLE) ? "/BLE" : "");
-
-    printf("silicon revision %d, ", chip_info.revision);
-
-    printf("%dMB %s flash\n", spi_flash_get_chip_size() / (1024 * 1024),
-            (chip_info.features & CHIP_FEATURE_EMB_FLASH) ? "embedded" : "external");
-
-    LCD_setup();
-
-    for (int i = 5; i >= 0; i--) {
-        printf("Restarting in %d seconds...\n", i);
-
-        LCD_clearDisplay(0);
-        LCD_setStr("Hello World", 0, 0, 1);
-        LCD_setStr("Driver stolen from Arduino  now on ESP32", 0, 10, 1);
-
-        LCD_setRect(0,LCD_HEIGHT-12,LCD_WIDTH, LCD_HEIGHT-1, 1, 1);
-        char buf[25];
-        sprintf(buf, "Reboot in %d s", i);
-        LCD_setStr(buf, 4, LCD_HEIGHT - 10, 0);
-        LCD_updateDisplay();
-
-        vTaskDelay(900 / portTICK_PERIOD_MS);
-    }
-    printf("Restarting now.\n");
-    fflush(stdout);
-    esp_restart();
-}
diff --git a/main/knob.c b/main/knob.c
new file mode 100644
index 0000000..6526a92
--- /dev/null
+++ b/main/knob.c
@@ -0,0 +1,136 @@
+#include <driver/gpio.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include "knob.h"
+#include "gui.h"
+
+const int pushPin = 5;
+const int wheelPin1 = 18;
+const int wheelPin2 = 23;
+
+static void handle_pushbtn(void *arg);
+static void handle_wheel(void *arg);
+
+void knob_init() {
+    printf("Knob init\n");
+
+    gpio_config_t output = {
+        .pin_bit_mask = (1<<pushPin) | (1 << wheelPin1) | (1 << wheelPin2),
+        .mode = GPIO_MODE_INPUT,
+        .pull_up_en = 1,
+        .intr_type = GPIO_INTR_ANYEDGE,
+    };
+    gpio_config(&output);
+
+    gpio_install_isr_service(0);
+    gpio_intr_enable(pushPin);
+    gpio_intr_enable(wheelPin1);
+    gpio_intr_enable(wheelPin2);
+
+    gpio_isr_handler_add(pushPin, handle_pushbtn, (void *)0);
+    gpio_isr_handler_add(wheelPin1, handle_wheel, (void *)0);
+    gpio_isr_handler_add(wheelPin2, handle_wheel, (void *)1);
+}
+
+enum state {
+    S_11 = 0,
+
+    S_FWD_1_01 = 1,
+    S_FWD_2_00 = 2,
+    S_FWD_3_10 = 3,
+
+    S_BCK_1_10 = 4,
+    S_BCK_2_00 = 5,
+    S_BCK_3_01 = 6,
+
+    S_ILLEGAL  = 7,
+};
+
+#define SW_FWD 0b10000000
+#define SW_BCK 0b01000000
+
+static enum state wheelState = S_11;
+
+const uint8_t switch_table[28] = {
+    /* -- S_11 -- */
+    S_ILLEGAL, /* 00 ILLEGAL */
+    S_FWD_1_01, /* 01 ADVANCE */
+    S_BCK_1_10, /* 10 BACK */
+    S_11, /* 11 */
+
+    /* -- S_FWD_1_01 -- */
+    S_FWD_2_00, /* 00 ADVANCE */
+    S_FWD_1_01, /* 01 */
+    S_ILLEGAL,  /* 10 ILLEGAL */
+    S_11,       /* 11 ABORT */
+
+    /* -- S_FWD_2_00 -- */
+    S_FWD_2_00, /* 00 */
+    S_FWD_1_01, /* 01 ABORT */
+    S_FWD_3_10, /* 10 ADVANCE */
+    S_ILLEGAL,  /* 11 ILLEGAL */
+
+    /* -- S_FWD_3_10 -- */
+    S_FWD_2_00, /* 00 ABORT */
+    S_ILLEGAL,  /* 01 ILLEGAL */
+    S_FWD_3_10, /* 10 */
+    SW_FWD | S_11, /* 11 ADVANCE */
+
+    /* -- S_BCK_1_10 -- */
+    S_BCK_2_00, /* 00 ADVANCE */
+    S_ILLEGAL, /* 01 ILLEGAL */
+    S_BCK_1_10, /* 10 */
+    S_11,       /* 11 ABORT */
+
+    /* -- S_BCK_2_00 -- */
+    S_BCK_2_00, /* 00 */
+    S_BCK_3_01, /* 01 */
+    S_BCK_1_10, /* 10 ABORT */
+    S_ILLEGAL, /* 11 */
+
+    /* -- S_BCK_3_01 -- */
+    S_BCK_2_00, /* 00 */
+    S_BCK_3_01, /* 01 */
+    S_ILLEGAL, /* 10 */
+    SW_BCK | S_11, /* 11 */
+};
+
+static void handle_wheel(void *arg) {
+    const uint32_t inputs = gpio_input_get();
+    const uint8_t ab =
+        (((inputs >> wheelPin2) & 1) << 1) |
+        ((inputs >> wheelPin1) & 1);
+
+    if (wheelState == S_ILLEGAL) {
+        if (ab != 0b11) {
+            return;
+        }
+    }
+
+    uint8_t next = switch_table[wheelState*4 + ab];
+
+    const bool forward = next & SW_FWD;
+    const bool backward = next & SW_BCK;
+    next &= ~(SW_FWD | SW_BCK);
+
+    wheelState = next;
+
+    if (forward || backward) {
+        BaseType_t higherWoken = 0;
+        xTaskNotifyFromISR(hGuiThread, forward | (backward << 1), eSetValueWithOverwrite, &higherWoken);
+        if (higherWoken) {
+            portYIELD_FROM_ISR();
+        }
+    }
+}
+
+static void handle_pushbtn(void *arg) {
+    const uint32_t inputs = gpio_input_get();
+    if ((inputs & (1 << pushPin)) == 0) {
+        BaseType_t higherWoken = 0;
+        xTaskNotifyFromISR(hGuiThread, 0b100, eSetValueWithOverwrite, &higherWoken);
+        if (higherWoken) {
+            portYIELD_FROM_ISR();
+        }
+    }
+}
diff --git a/main/knob.h b/main/knob.h
new file mode 100644
index 0000000..1ff6bb9
--- /dev/null
+++ b/main/knob.h
@@ -0,0 +1,7 @@
+#ifndef KNOB_H
+#define KNOB_H
+
+void knob_init();
+
+
+#endif //KNOB_H
diff --git a/main/nokia.c b/main/nokia.c
index 4eadd5d..7b1fa62 100644
--- a/main/nokia.c
+++ b/main/nokia.c
@@ -18,6 +18,8 @@ static const int sclkPin = 13;  // SCLK - Serial clock, pin 7 on LCD.
 #define LCD_COMMAND  0
 #define LCD_DATA     1
 
+#define DEFAULT_CONTRAST 48
+
 static spi_device_handle_t hSPI;
 
 /* Font table:
@@ -28,197 +30,102 @@ per character. */
 static const uint8_t ASCII[][5] = {
     // First 32 characters (0x00-0x19) are ignored. These are
     // non-displayable, control characters.
-    {0x00, 0x00, 0x00, 0x00, 0x00} // 0x20
-    ,
-    {0x00, 0x00, 0x5f, 0x00, 0x00} // 0x21 !
-    ,
-    {0x00, 0x07, 0x00, 0x07, 0x00} // 0x22 "
-    ,
-    {0x14, 0x7f, 0x14, 0x7f, 0x14} // 0x23 #
-    ,
-    {0x24, 0x2a, 0x7f, 0x2a, 0x12} // 0x24 $
-    ,
-    {0x23, 0x13, 0x08, 0x64, 0x62} // 0x25 %
-    ,
-    {0x36, 0x49, 0x55, 0x22, 0x50} // 0x26 &
-    ,
-    {0x00, 0x05, 0x03, 0x00, 0x00} // 0x27 '
-    ,
-    {0x00, 0x1c, 0x22, 0x41, 0x00} // 0x28 (
-    ,
-    {0x00, 0x41, 0x22, 0x1c, 0x00} // 0x29 )
-    ,
-    {0x14, 0x08, 0x3e, 0x08, 0x14} // 0x2a *
-    ,
-    {0x08, 0x08, 0x3e, 0x08, 0x08} // 0x2b +
-    ,
-    {0x00, 0x50, 0x30, 0x00, 0x00} // 0x2c ,
-    ,
-    {0x08, 0x08, 0x08, 0x08, 0x08} // 0x2d -
-    ,
-    {0x00, 0x60, 0x60, 0x00, 0x00} // 0x2e .
-    ,
-    {0x20, 0x10, 0x08, 0x04, 0x02} // 0x2f /
-    ,
-    {0x3e, 0x51, 0x49, 0x45, 0x3e} // 0x30 0
-    ,
-    {0x00, 0x42, 0x7f, 0x40, 0x00} // 0x31 1
-    ,
-    {0x42, 0x61, 0x51, 0x49, 0x46} // 0x32 2
-    ,
-    {0x21, 0x41, 0x45, 0x4b, 0x31} // 0x33 3
-    ,
-    {0x18, 0x14, 0x12, 0x7f, 0x10} // 0x34 4
-    ,
-    {0x27, 0x45, 0x45, 0x45, 0x39} // 0x35 5
-    ,
-    {0x3c, 0x4a, 0x49, 0x49, 0x30} // 0x36 6
-    ,
-    {0x01, 0x71, 0x09, 0x05, 0x03} // 0x37 7
-    ,
-    {0x36, 0x49, 0x49, 0x49, 0x36} // 0x38 8
-    ,
-    {0x06, 0x49, 0x49, 0x29, 0x1e} // 0x39 9
-    ,
-    {0x00, 0x36, 0x36, 0x00, 0x00} // 0x3a :
-    ,
-    {0x00, 0x56, 0x36, 0x00, 0x00} // 0x3b ;
-    ,
-    {0x08, 0x14, 0x22, 0x41, 0x00} // 0x3c <
-    ,
-    {0x14, 0x14, 0x14, 0x14, 0x14} // 0x3d =
-    ,
-    {0x00, 0x41, 0x22, 0x14, 0x08} // 0x3e >
-    ,
-    {0x02, 0x01, 0x51, 0x09, 0x06} // 0x3f ?
-    ,
-    {0x32, 0x49, 0x79, 0x41, 0x3e} // 0x40 @
-    ,
-    {0x7e, 0x11, 0x11, 0x11, 0x7e} // 0x41 A
-    ,
-    {0x7f, 0x49, 0x49, 0x49, 0x36} // 0x42 B
-    ,
-    {0x3e, 0x41, 0x41, 0x41, 0x22} // 0x43 C
-    ,
-    {0x7f, 0x41, 0x41, 0x22, 0x1c} // 0x44 D
-    ,
-    {0x7f, 0x49, 0x49, 0x49, 0x41} // 0x45 E
-    ,
-    {0x7f, 0x09, 0x09, 0x09, 0x01} // 0x46 F
-    ,
-    {0x3e, 0x41, 0x49, 0x49, 0x7a} // 0x47 G
-    ,
-    {0x7f, 0x08, 0x08, 0x08, 0x7f} // 0x48 H
-    ,
-    {0x00, 0x41, 0x7f, 0x41, 0x00} // 0x49 I
-    ,
-    {0x20, 0x40, 0x41, 0x3f, 0x01} // 0x4a J
-    ,
-    {0x7f, 0x08, 0x14, 0x22, 0x41} // 0x4b K
-    ,
-    {0x7f, 0x40, 0x40, 0x40, 0x40} // 0x4c L
-    ,
-    {0x7f, 0x02, 0x0c, 0x02, 0x7f} // 0x4d M
-    ,
-    {0x7f, 0x04, 0x08, 0x10, 0x7f} // 0x4e N
-    ,
-    {0x3e, 0x41, 0x41, 0x41, 0x3e} // 0x4f O
-    ,
-    {0x7f, 0x09, 0x09, 0x09, 0x06} // 0x50 P
-    ,
-    {0x3e, 0x41, 0x51, 0x21, 0x5e} // 0x51 Q
-    ,
-    {0x7f, 0x09, 0x19, 0x29, 0x46} // 0x52 R
-    ,
-    {0x46, 0x49, 0x49, 0x49, 0x31} // 0x53 S
-    ,
-    {0x01, 0x01, 0x7f, 0x01, 0x01} // 0x54 T
-    ,
-    {0x3f, 0x40, 0x40, 0x40, 0x3f} // 0x55 U
-    ,
-    {0x1f, 0x20, 0x40, 0x20, 0x1f} // 0x56 V
-    ,
-    {0x3f, 0x40, 0x38, 0x40, 0x3f} // 0x57 W
-    ,
-    {0x63, 0x14, 0x08, 0x14, 0x63} // 0x58 X
-    ,
-    {0x07, 0x08, 0x70, 0x08, 0x07} // 0x59 Y
-    ,
-    {0x61, 0x51, 0x49, 0x45, 0x43} // 0x5a Z
-    ,
-    {0x00, 0x7f, 0x41, 0x41, 0x00} // 0x5b [
-    ,
-    {0x02, 0x04, 0x08, 0x10, 0x20} // 0x5c \ (keep this to escape the backslash)
-    ,
-    {0x00, 0x41, 0x41, 0x7f, 0x00} // 0x5d ]
-    ,
-    {0x04, 0x02, 0x01, 0x02, 0x04} // 0x5e ^
-    ,
-    {0x40, 0x40, 0x40, 0x40, 0x40} // 0x5f _
-    ,
-    {0x00, 0x01, 0x02, 0x04, 0x00} // 0x60 `
-    ,
-    {0x20, 0x54, 0x54, 0x54, 0x78} // 0x61 a
-    ,
-    {0x7f, 0x48, 0x44, 0x44, 0x38} // 0x62 b
-    ,
-    {0x38, 0x44, 0x44, 0x44, 0x20} // 0x63 c
-    ,
-    {0x38, 0x44, 0x44, 0x48, 0x7f} // 0x64 d
-    ,
-    {0x38, 0x54, 0x54, 0x54, 0x18} // 0x65 e
-    ,
-    {0x08, 0x7e, 0x09, 0x01, 0x02} // 0x66 f
-    ,
-    {0x0c, 0x52, 0x52, 0x52, 0x3e} // 0x67 g
-    ,
-    {0x7f, 0x08, 0x04, 0x04, 0x78} // 0x68 h
-    ,
-    {0x00, 0x44, 0x7d, 0x40, 0x00} // 0x69 i
-    ,
-    {0x20, 0x40, 0x44, 0x3d, 0x00} // 0x6a j
-    ,
-    {0x7f, 0x10, 0x28, 0x44, 0x00} // 0x6b k
-    ,
-    {0x00, 0x41, 0x7f, 0x40, 0x00} // 0x6c l
-    ,
-    {0x7c, 0x04, 0x18, 0x04, 0x78} // 0x6d m
-    ,
-    {0x7c, 0x08, 0x04, 0x04, 0x78} // 0x6e n
-    ,
-    {0x38, 0x44, 0x44, 0x44, 0x38} // 0x6f o
-    ,
-    {0x7c, 0x14, 0x14, 0x14, 0x08} // 0x70 p
-    ,
-    {0x08, 0x14, 0x14, 0x18, 0x7c} // 0x71 q
-    ,
-    {0x7c, 0x08, 0x04, 0x04, 0x08} // 0x72 r
-    ,
-    {0x48, 0x54, 0x54, 0x54, 0x20} // 0x73 s
-    ,
-    {0x04, 0x3f, 0x44, 0x40, 0x20} // 0x74 t
-    ,
-    {0x3c, 0x40, 0x40, 0x20, 0x7c} // 0x75 u
-    ,
-    {0x1c, 0x20, 0x40, 0x20, 0x1c} // 0x76 v
-    ,
-    {0x3c, 0x40, 0x30, 0x40, 0x3c} // 0x77 w
-    ,
-    {0x44, 0x28, 0x10, 0x28, 0x44} // 0x78 x
-    ,
-    {0x0c, 0x50, 0x50, 0x50, 0x3c} // 0x79 y
-    ,
-    {0x44, 0x64, 0x54, 0x4c, 0x44} // 0x7a z
-    ,
-    {0x00, 0x08, 0x36, 0x41, 0x00} // 0x7b {
-    ,
-    {0x00, 0x00, 0x7f, 0x00, 0x00} // 0x7c |
-    ,
-    {0x00, 0x41, 0x36, 0x08, 0x00} // 0x7d }
-    ,
-    {0x10, 0x08, 0x08, 0x10, 0x08} // 0x7e ~
-    ,
-    {0x78, 0x46, 0x41, 0x46, 0x78} // 0x7f DEL
+    {0x00, 0x00, 0x00, 0x00, 0x00}, // 0x20
+    {0x00, 0x00, 0x5f, 0x00, 0x00}, // 0x21 !
+    {0x00, 0x07, 0x00, 0x07, 0x00}, // 0x22 "
+    {0x14, 0x7f, 0x14, 0x7f, 0x14}, // 0x23 #
+    {0x24, 0x2a, 0x7f, 0x2a, 0x12}, // 0x24 $
+    {0x23, 0x13, 0x08, 0x64, 0x62}, // 0x25 %
+    {0x36, 0x49, 0x55, 0x22, 0x50}, // 0x26 &
+    {0x00, 0x05, 0x03, 0x00, 0x00}, // 0x27 '
+    {0x00, 0x1c, 0x22, 0x41, 0x00}, // 0x28 (
+    {0x00, 0x41, 0x22, 0x1c, 0x00}, // 0x29 )
+    {0x14, 0x08, 0x3e, 0x08, 0x14}, // 0x2a *
+    {0x08, 0x08, 0x3e, 0x08, 0x08}, // 0x2b +
+    {0x00, 0x50, 0x30, 0x00, 0x00}, // 0x2c ,
+    {0x08, 0x08, 0x08, 0x08, 0x08}, // 0x2d -
+    {0x00, 0x60, 0x60, 0x00, 0x00}, // 0x2e .
+    {0x20, 0x10, 0x08, 0x04, 0x02}, // 0x2f /
+    {0x3e, 0x51, 0x49, 0x45, 0x3e}, // 0x30 0
+    {0x00, 0x42, 0x7f, 0x40, 0x00}, // 0x31 1
+    {0x42, 0x61, 0x51, 0x49, 0x46}, // 0x32 2
+    {0x21, 0x41, 0x45, 0x4b, 0x31}, // 0x33 3
+    {0x18, 0x14, 0x12, 0x7f, 0x10}, // 0x34 4
+    {0x27, 0x45, 0x45, 0x45, 0x39}, // 0x35 5
+    {0x3c, 0x4a, 0x49, 0x49, 0x30}, // 0x36 6
+    {0x01, 0x71, 0x09, 0x05, 0x03}, // 0x37 7
+    {0x36, 0x49, 0x49, 0x49, 0x36}, // 0x38 8
+    {0x06, 0x49, 0x49, 0x29, 0x1e}, // 0x39 9
+    {0x00, 0x36, 0x36, 0x00, 0x00}, // 0x3a :
+    {0x00, 0x56, 0x36, 0x00, 0x00}, // 0x3b ;
+    {0x08, 0x14, 0x22, 0x41, 0x00}, // 0x3c <
+    {0x14, 0x14, 0x14, 0x14, 0x14}, // 0x3d =
+    {0x00, 0x41, 0x22, 0x14, 0x08}, // 0x3e >
+    {0x02, 0x01, 0x51, 0x09, 0x06}, // 0x3f ?
+    {0x32, 0x49, 0x79, 0x41, 0x3e}, // 0x40 @
+    {0x7e, 0x11, 0x11, 0x11, 0x7e}, // 0x41 A
+    {0x7f, 0x49, 0x49, 0x49, 0x36}, // 0x42 B
+    {0x3e, 0x41, 0x41, 0x41, 0x22}, // 0x43 C
+    {0x7f, 0x41, 0x41, 0x22, 0x1c}, // 0x44 D
+    {0x7f, 0x49, 0x49, 0x49, 0x41}, // 0x45 E
+    {0x7f, 0x09, 0x09, 0x09, 0x01}, // 0x46 F
+    {0x3e, 0x41, 0x49, 0x49, 0x7a}, // 0x47 G
+    {0x7f, 0x08, 0x08, 0x08, 0x7f}, // 0x48 H
+    {0x00, 0x41, 0x7f, 0x41, 0x00}, // 0x49 I
+    {0x20, 0x40, 0x41, 0x3f, 0x01}, // 0x4a J
+    {0x7f, 0x08, 0x14, 0x22, 0x41}, // 0x4b K
+    {0x7f, 0x40, 0x40, 0x40, 0x40}, // 0x4c L
+    {0x7f, 0x02, 0x0c, 0x02, 0x7f}, // 0x4d M
+    {0x7f, 0x04, 0x08, 0x10, 0x7f}, // 0x4e N
+    {0x3e, 0x41, 0x41, 0x41, 0x3e}, // 0x4f O
+    {0x7f, 0x09, 0x09, 0x09, 0x06}, // 0x50 P
+    {0x3e, 0x41, 0x51, 0x21, 0x5e}, // 0x51 Q
+    {0x7f, 0x09, 0x19, 0x29, 0x46}, // 0x52 R
+    {0x46, 0x49, 0x49, 0x49, 0x31}, // 0x53 S
+    {0x01, 0x01, 0x7f, 0x01, 0x01}, // 0x54 T
+    {0x3f, 0x40, 0x40, 0x40, 0x3f}, // 0x55 U
+    {0x1f, 0x20, 0x40, 0x20, 0x1f}, // 0x56 V
+    {0x3f, 0x40, 0x38, 0x40, 0x3f}, // 0x57 W
+    {0x63, 0x14, 0x08, 0x14, 0x63}, // 0x58 X
+    {0x07, 0x08, 0x70, 0x08, 0x07}, // 0x59 Y
+    {0x61, 0x51, 0x49, 0x45, 0x43}, // 0x5a Z
+    {0x00, 0x7f, 0x41, 0x41, 0x00}, // 0x5b [
+    {0x02, 0x04, 0x08, 0x10, 0x20}, // 0x5c \ (keep this to escape the backslash)
+    {0x00, 0x41, 0x41, 0x7f, 0x00}, // 0x5d ]
+    {0x04, 0x02, 0x01, 0x02, 0x04}, // 0x5e ^
+    {0x40, 0x40, 0x40, 0x40, 0x40}, // 0x5f _
+    {0x00, 0x01, 0x02, 0x04, 0x00}, // 0x60 `
+    {0x20, 0x54, 0x54, 0x54, 0x78}, // 0x61 a
+    {0x7f, 0x48, 0x44, 0x44, 0x38}, // 0x62 b
+    {0x38, 0x44, 0x44, 0x44, 0x20}, // 0x63 c
+    {0x38, 0x44, 0x44, 0x48, 0x7f}, // 0x64 d
+    {0x38, 0x54, 0x54, 0x54, 0x18}, // 0x65 e
+    {0x08, 0x7e, 0x09, 0x01, 0x02}, // 0x66 f
+    {0x0c, 0x52, 0x52, 0x52, 0x3e}, // 0x67 g
+    {0x7f, 0x08, 0x04, 0x04, 0x78}, // 0x68 h
+    {0x00, 0x44, 0x7d, 0x40, 0x00}, // 0x69 i
+    {0x20, 0x40, 0x44, 0x3d, 0x00}, // 0x6a j
+    {0x7f, 0x10, 0x28, 0x44, 0x00}, // 0x6b k
+    {0x00, 0x41, 0x7f, 0x40, 0x00}, // 0x6c l
+    {0x7c, 0x04, 0x18, 0x04, 0x78}, // 0x6d m
+    {0x7c, 0x08, 0x04, 0x04, 0x78}, // 0x6e n
+    {0x38, 0x44, 0x44, 0x44, 0x38}, // 0x6f o
+    {0x7c, 0x14, 0x14, 0x14, 0x08}, // 0x70 p
+    {0x08, 0x14, 0x14, 0x18, 0x7c}, // 0x71 q
+    {0x7c, 0x08, 0x04, 0x04, 0x08}, // 0x72 r
+    {0x48, 0x54, 0x54, 0x54, 0x20}, // 0x73 s
+    {0x04, 0x3f, 0x44, 0x40, 0x20}, // 0x74 t
+    {0x3c, 0x40, 0x40, 0x20, 0x7c}, // 0x75 u
+    {0x1c, 0x20, 0x40, 0x20, 0x1c}, // 0x76 v
+    {0x3c, 0x40, 0x30, 0x40, 0x3c}, // 0x77 w
+    {0x44, 0x28, 0x10, 0x28, 0x44}, // 0x78 x
+    {0x0c, 0x50, 0x50, 0x50, 0x3c}, // 0x79 y
+    {0x44, 0x64, 0x54, 0x4c, 0x44}, // 0x7a z
+    {0x00, 0x08, 0x36, 0x41, 0x00}, // 0x7b {
+    {0x00, 0x00, 0x7f, 0x00, 0x00}, // 0x7c |
+    {0x00, 0x41, 0x36, 0x08, 0x00}, // 0x7d }
+    {0x10, 0x08, 0x08, 0x10, 0x08}, // 0x7e ~
+    {0x78, 0x46, 0x41, 0x46, 0x78}, // 0x7f DEL
 };
 
 /* The displayMap variable stores a buffer representation of the
@@ -235,50 +142,7 @@ to the PCD8544.
 
 Because the PCD8544 won't let us write individual pixels at a
 time, this is how we can make targeted changes to the display. */
-static uint8_t displayMap[LCD_WIDTH * LCD_HEIGHT / 8] = {
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (0,0)->(11,7) ~ These 12 bytes cover an 8x12 block in the left corner of the display
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (12,0)->(23,7)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xE0, // (24,0)->(35,7)
-    0xF0, 0xF8, 0xFC, 0xFC, 0xFE, 0xFE, 0xFE, 0xFE, 0x1E, 0x0E, 0x02, 0x00, // (36,0)->(47,7)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (48,0)->(59,7)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (60,0)->(71,7)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (72,0)->(83,7)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (0,8)->(11,15)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (12,8)->(23,15)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, // (24,8)->(35,15)
-    0x0F, 0x1F, 0x3F, 0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFC, 0xF8, // (36,8)->(47,15)
-    0xF8, 0xF0, 0xF8, 0xFE, 0xFE, 0xFC, 0xF8, 0xE0, 0x00, 0x00, 0x00, 0x00, // (48,8)->(59,15)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (60,8)->(71,15)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (72,8)->(83,15)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (0,16)->(11,23)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (12,16)->(23,23)
-    0x00, 0x00, 0xF8, 0xFC, 0xFE, 0xFE, 0xFF, 0xFF, 0xF3, 0xE0, 0xE0, 0xC0, // (24,16)->(35,23)
-    0xC0, 0xC0, 0xE0, 0xE0, 0xF1, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // (36,16)->(47,23)
-    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x3E, 0x00, 0x00, 0x00, // (48,16)->(59,23)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (60,16)->(71,23)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (72,16)->(83,23)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (0,24)->(11,31)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (12,24)->(23,31)
-    0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // (24,24)->(35,31)
-    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, // (36,24)->(47,31)
-    0xFF, 0xFF, 0xFF, 0x7F, 0x3F, 0x1F, 0x07, 0x01, 0x00, 0x00, 0x00, 0x00, // (48,24)->(59,31)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (60,24)->(71,31)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (72,24)->(83,31)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (0,32)->(11,39)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (12,32)->(23,39)
-    0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x7F, 0x3F, 0x1F, // (24,32)->(35,39)
-    0x0F, 0x0F, 0x0F, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x03, 0x03, // (36,32)->(47,39)
-    0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (48,32)->(59,39)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (60,32)->(71,39)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (72,32)->(83,39)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (0,40)->(11,47)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (12,40)->(23,47)
-    0x00, 0x00, 0x3F, 0x1F, 0x0F, 0x07, 0x03, 0x01, 0x00, 0x00, 0x00, 0x00, // (24,40)->(35,47)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (36,40)->(47,47)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (48,40)->(59,47)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (60,40)->(71,47)
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // (72,40)->(83,47) !!! The bottom right pixel!
-};
+static uint8_t displayMap[LCD_WIDTH * LCD_HEIGHT / 8];
 
 // There are two memory banks in the LCD, data/RAM and commands.
 // This function sets the DC pin high or low depending, and then
@@ -583,6 +447,9 @@ void lcd_spi_pre_transfer_callback(spi_transaction_t *t)
 //This sends the magical commands to the PCD8544
 void LCD_setup(void)
 {
+    // clear the display array
+    LCD_clearDisplay(0);
+
     gpio_config_t output = {
         .pin_bit_mask = (1<<scePin) | (1<<rstPin) | (1<<dcPin) | (1<<sdinPin) | (1<<sclkPin),
         .mode = GPIO_MODE_OUTPUT
@@ -617,23 +484,26 @@ void LCD_setup(void)
     ESP_ERROR_CHECK(ret);
 
     spi_device_acquire_bus(hSPI, portMAX_DELAY);
-
-    //Reset the LCD to a known state
-    gpio_set_level(rstPin, 0);
-    gpio_set_level(rstPin, 1);
-
-    const uint8_t magic[6] = {
-        0x21, // Tell LCD extended commands follow
-        0x80 + 40, // Set LCD Vop (Contrast)
-        0x04, // Set Temp coefficent
-        0x14, // LCD bias mode 1:48 (try 0x13)
-        //We must send 0x20 before modifying the display control mode
-        0x20, // Clear extended option
-        0x0C, // Set display control, normal mode.
-    };
-    LCD_SendBytes(LCD_COMMAND, &magic[0], 6);
-
+    {
+        //Reset the LCD to a known state
+        gpio_set_level(rstPin, 0);
+        gpio_set_level(rstPin, 1);
+
+        const uint8_t magic[6] = {
+            0x21, // Tell LCD extended commands follow
+            0x80 + DEFAULT_CONTRAST, // Set LCD Vop (Contrast)
+            0x04, // Set Temp coefficent
+            0x14, // LCD bias mode 1:48 (try 0x13)
+            //We must send 0x20 before modifying the display control mode
+            0x20, // Clear extended option
+            0x0C, // Set display control, normal mode.
+        };
+        LCD_SendBytes(LCD_COMMAND, &magic[0], 6);
+    }
     spi_device_release_bus(hSPI);
+
+    // show the blank screen (display is in indefined state after boot)
+    LCD_updateDisplay();
 }