From 60b9b3b5087872de26dfa613e1922cb79fdae651 Mon Sep 17 00:00:00 2001
From: Eugene <eugene@corks.su>
Date: Mon, 26 Jan 2026 16:56:02 +0300
Subject: [PATCH] fixed distance display

---
 stairs_arduino.ino | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/stairs_arduino.ino b/stairs_arduino.ino
index fa4dd00..be45888 100644
--- a/stairs_arduino.ino
+++ b/stairs_arduino.ino
@@ -2373,8 +2373,10 @@ void displayDistanceOnModules(float distance, int startModule) {
   int digitCount = 0;
   
   if (meters == 0) {
+    // Show "00" for zero
     digits[0] = 0;
-    digitCount = 1;
+    digits[1] = 0;
+    digitCount = 2;
   } else {
     int temp = meters;
     while (temp > 0 && digitCount < availableModules) {
@@ -2382,6 +2384,11 @@ void displayDistanceOnModules(float distance, int startModule) {
       temp /= 10;
       digitCount++;
     }
+    // Ensure minimum 2 digits (show leading zero for values < 10)
+    if (digitCount == 1 && availableModules >= 2) {
+      digits[1] = 0; // Leading zero
+      digitCount = 2;
+    }
   }
   
   // Cache last displayed digits per module
@@ -2414,8 +2421,9 @@ void displayDistanceOnModules(float distance, int startModule) {
   }
   
   if (needsUpdate) {
-    // Clear only the modules we'll actually use (prevents flashing)
-    for (int i = 0; i < digitCount && (startModule + i) < MATRIX_MODULES; i++) {
+    // Clear modules - include any extra modules from previous larger digit count
+    int modulesToClear = (digitCount > lastDigitCount) ? digitCount : lastDigitCount;
+    for (int i = 0; i < modulesToClear && (startModule + i) < MATRIX_MODULES; i++) {
       matrix.clearDisplay(startModule + i);
     }