diff --git a/buttons.c b/buttons.c
new file mode 100644
index 0000000..5215dc0
--- /dev/null
+++ b/buttons.c
@@ -0,0 +1,28 @@
+#include "const.h"
+#include "state.h"
+#include "vco.h"
+#include <pico/types.h>
+#include "hardware/gpio.h"
+
+
+void handle_vco_change(uint gpio, uint32_t events) {
+  if (gpio == VCO_BUTTON && (events & GPIO_IRQ_EDGE_RISE)) {
+        if (state.vco_mode == VCO_SAW) {
+                state.vco_mode = VCO_SINE;
+        } otherwise {
+              state.vco_mode++;  
+        }
+  }
+}
+
+void update_button(uint pin, bool *button_state) {
+        if(gpio_get(pin) != *button_state) {
+                *button_state=!*button_state;
+        }
+}
+
+void update_buttons() {
+        update_button(QUANT_BUTTON,&state.quant_enabled);
+
+
+}
\ No newline at end of file
diff --git a/buttons.h b/buttons.h
new file mode 100644
index 0000000..47a4a21
--- /dev/null
+++ b/buttons.h
@@ -0,0 +1,3 @@
+#pragma once
+#include <pico/types.h>
+void handle_vco_change(uint gpio, uint32_t events);
\ No newline at end of file
diff --git a/const.h b/const.h
index 6aac508..a446624 100644
--- a/const.h
+++ b/const.h
@@ -16,3 +16,4 @@
 
 #define SAMPLE_RATE 44100.0f
 
+#define otherwise else
diff --git a/main.cc b/main.cc
index 56e473f..3971fa4 100644
--- a/main.cc
+++ b/main.cc
@@ -1,3 +1,4 @@
+#include "buttons.h"
 #include "macro.h"
 #include "pico/stdlib.h"
 #include <hardware/gpio.h>
@@ -36,6 +37,9 @@ void init_all() {
 		 adc_gpio_init(adc_gpio[i]);
 		 adc_select_input(i);
 	}
+
+	gpio_pull_down(VCO_BUTTON);
+	gpio_set_irq_enabled_with_callback(VCO_BUTTON, GPIO_IRQ_EDGE_RISE, true, &handle_vco_change);
 }
 
 daisysp::Oscillator osc;