diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4092bfd..a574f0c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,6 +58,7 @@ target_link_libraries(raspi_keyer
   hardware_pwm
   pico_flash
   pico_multicore
+  hardware_adc
   tinyusb_device
   tinyusb_board
   hardware_pio
diff --git a/src/raspi_keyer.cpp b/src/raspi_keyer.cpp
index f3acf9b..8c01d96 100644
--- a/src/raspi_keyer.cpp
+++ b/src/raspi_keyer.cpp
@@ -1,6 +1,8 @@
+#include <cmath>
 #include <stdio.h>
 
 #include "bsp/board.h"
+#include "hardware/adc.h"
 #include "pico/multicore.h"
 #include "pico/stdlib.h"
 #include "pico/util/queue.h"
@@ -21,6 +23,7 @@ extern const uint RIGHT_PADDLE_PIN = 15;
 extern const uint BUZZER_PIN = 18;
 extern const uint CW_OUT_PIN = 17;
 extern const uint AUDIO_OUT_PIN = 16;
+extern const uint ADC_PIN = 26;
 
 // Stuff for communicating between cores
 enum class KeyerQueueCommand {
@@ -54,11 +57,17 @@ void setup()
     gpio_init(CW_OUT_PIN);
     gpio_set_dir(CW_OUT_PIN, GPIO_OUT);
     gpio_put(CW_OUT_PIN, 0);
+
+    // Setup ADC
+    adc_init();
+    gpio_init(ADC_PIN);
+    adc_select_input(0);
 }
 
 /* Let's do all the keying stuff in the second core, so there are no timing problems. */
 void core1_main()
 {
+    flash_safe_execute_core_init();
     printf("Hello from core1!\n");
     KeyerQueueData data;
     queue_remove_blocking(&keyerQueue, &data);
@@ -89,15 +98,13 @@ void core1_main()
     }
 }
 
-[[maybe_unused]]
-static void echo_serial_port(uint8_t itf, uint8_t buf[], uint32_t count)
+[[maybe_unused]] static void echo_serial_port(uint8_t itf, uint8_t buf[], uint32_t count)
 {
-  for(uint32_t i=0; i<count; i++)
-  {
-    tud_cdc_n_write_char(itf, buf[i]);
-  }
+    for (uint32_t i = 0; i < count; i++) {
+        tud_cdc_n_write_char(itf, buf[i]);
+    }
 
-  tud_cdc_n_write_flush(itf);
+    tud_cdc_n_write_flush(itf);
 }
 
 void cdc_task()
@@ -111,11 +118,11 @@ void cdc_task()
         if (count > 1) {
             printf("Command received …\n");
             switch (buf[0]) {
-                case 0: // ADMIN COMMAND
+            case 0: // ADMIN COMMAND
                 switch (buf[1]) {
-                    case 2: // Host Open
-                    // TODO: send back revision code
-                    default:
+                case 2: // Host Open
+                // TODO: send back revision code
+                default:
                     printf("Unknown admin command.\n");
                 }
                 break;
@@ -126,9 +133,27 @@ void cdc_task()
     }
 }
 
+/* Returns the voltage level in percent (3,3V == 100%) */
+float potiRead()
+{
+    // 12-bit conversion, assume max value == ADC_VREF == 3.3 V
+    const float conversion_factor = 3.3f / (1 << 12);
+    float voltage = adc_read() * conversion_factor;
+
+    return voltage * 100 / 3.3;
+}
+
+/* Calculates the WPM speed from the volt percentage */
+uint8_t calcWPM(float percent, uint8_t wpmMin, uint8_t wpmMax)
+{
+    auto wpm = (percent * (wpmMax - wpmMin) / 100) + wpmMin;
+    uint8_t result = static_cast<uint8_t>(std::round(wpm));
+    return result;
+}
+
 int main()
 {
-    // timer_hw->dbgpause = 2; // workaround for problem with debug and sleep_ms
+    timer_hw->dbgpause = 0; // workaround for problem with debug and sleep_ms
     //  https://github.com/raspberrypi/pico-sdk/issues/1152#issuecomment-1418248639
 
     setup();
@@ -137,19 +162,36 @@ int main()
 
     printf("Hello from core0!\n");
 
-    Settings settings {read_settings()};
-    settings.wpm = 25; // TODO: remove!
+    //Settings settings {read_settings()};
+    Settings settings;
+    uint8_t currentWpm, lastWpm {0};
+    if (settings.wpm == 0) {
+        currentWpm = calcWPM(potiRead(), settings.wpmPotiMin, settings.wpmPotiMax);
+    } else {
+        currentWpm = settings.wpm;
+    }
+    lastWpm = currentWpm;
 
     queue_init(&keyerQueue, sizeof(KeyerQueueData), 2);
     multicore_reset_core1();
     multicore_launch_core1(core1_main);
 
-    KeyerQueueData keyerQueueData {KeyerQueueCommand::Run, settings.wpm, settings.mode};
+    KeyerQueueData keyerQueueData {KeyerQueueCommand::Run, currentWpm, settings.mode};
     queue_add_blocking(&keyerQueue, &keyerQueueData);
 
     while (true) {
         tud_task();
         cdc_task();
+
+        currentWpm = calcWPM(potiRead(), settings.wpmPotiMin, settings.wpmPotiMax);
+        if (currentWpm != lastWpm) {
+            KeyerQueueData keyerQueueData {KeyerQueueCommand::Config, currentWpm, settings.mode};
+            queue_add_blocking(&keyerQueue, &keyerQueueData);
+            printf("WPM has changed to: %d\n", currentWpm);
+            lastWpm = currentWpm;
+        }
+
+        busy_wait_ms(1000);
     }
 
     return 0;