diff --git a/tach/tach.ino b/tach/tach.ino
index 0458045..43c5caf 100644
--- a/tach/tach.ino
+++ b/tach/tach.ino
@@ -11,7 +11,7 @@
 Adafruit_7segment matrix = Adafruit_7segment();
 
 // --- Tachometer variables ---
-const int TACH_INTERRUPT_PIN = A0; // Or any other digital pin capable of interrupts
+const int TACH_INTERRUPT_PIN = 10; // Or any other digital pin capable of interrupts
 volatile unsigned long g_isr_pulse_count_total = 0; // ISR increments this continuously
 unsigned long g_main_last_pulse_count_snapshot = 0; // Main loop stores previous snapshot here
 unsigned long last_measurement_time = 0;