From 6dd175f63bddeb361942df0c2725f7974f1c6e7a Mon Sep 17 00:00:00 2001
From: Harald Barth <haba@kth.se>
Date: Mon, 19 Jun 2023 00:33:53 +0200
Subject: [PATCH] fix power change timer micros overflow

---
 GITHUB_SHA.h  | 2 +-
 MotorDriver.h | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/GITHUB_SHA.h b/GITHUB_SHA.h
index 8bd3812..41f732d 100644
--- a/GITHUB_SHA.h
+++ b/GITHUB_SHA.h
@@ -1 +1 @@
-#define GITHUB_SHA "devel-202306181725Z"
+#define GITHUB_SHA "devel-202306182233Z"
diff --git a/MotorDriver.h b/MotorDriver.h
index fe577bd..1eb4e95 100644
--- a/MotorDriver.h
+++ b/MotorDriver.h
@@ -190,9 +190,10 @@ class MotorDriver {
     // was really long ago (approx > 52min) advance counter approx 35 min so that
     // we are at 18 minutes again. Times for 32 bit unsigned long.
     inline unsigned long microsSinceLastPowerChange() {
-      unsigned long diff = micros() - lastPowerChange;
-      if (diff > (1UL << (6 *sizeof(unsigned long))))
-	lastPowerChange += 1UL << (4 * sizeof(unsigned long));
+      unsigned long now = micros();
+      unsigned long diff = now - lastPowerChange;
+      if (diff > (1UL << (7 *sizeof(unsigned long)))) // 2^(4*7)us = 268.4 seconds
+        lastPowerChange = now - 30000000UL;           // 30 seconds ago
       return diff;
     };
 #ifdef ANALOG_READ_INTERRUPT