From f32a91f034230aa190c685a1ffb4e099b198f199 Mon Sep 17 00:00:00 2001
From: pillar1989 <zuobaozhu@gmail.com>
Date: Tue, 28 Apr 2026 11:18:08 +0800
Subject: [PATCH] fix: restore correct COUNT values for DHT timing threshold
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Commit 69cabab9 incorrectly reduced all COUNT values, breaking DHT11
sensor reads on 16 MHz AVR (Arduino Uno R3) and likely other platforms.

COUNT is the threshold to distinguish '0' bits (~26µs pulse) from '1'
bits (~70µs pulse) in the DHT protocol. The reduced values caused all
bits to be read as '1', producing garbage data.

Restore the previously working values from before 69cabab9.

Fixes #27.
---
 DHT.h | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/DHT.h b/DHT.h
index 2a8999f..571aa6c 100644
--- a/DHT.h
+++ b/DHT.h
@@ -9,29 +9,29 @@
 
 // 8 MHz(ish) AVR ---------------------------------------------------------
 #if (F_CPU >= 7400000UL) && (F_CPU <= 9500000UL)
-    #define COUNT 1
+    #define COUNT 3
     // 16 MHz(ish) AVR --------------------------------------------------------
 #elif (F_CPU == 10000000L)
-    #define COUNT 1
+    #define COUNT 3
 #elif (F_CPU >= 15400000UL) && (F_CPU <= 19000000L)
-    #define COUNT 2
+    #define COUNT 6
 #elif (F_CPU == 20000000L)
-    #define COUNT 2
+    #define COUNT 6
 #elif (F_CPU == 40000000L)
-    #define COUNT 4
+    #define COUNT 10
     // 48MHz SAMD21J18A (Sodaq Explorer)
 #elif (F_CPU == 48000000UL)
-    #define COUNT 5
-    // 64MHz NRF52840 
+    #define COUNT 18
+    // 64MHz NRF52840
 #elif (F_CPU == 64000000UL)
-    #define COUNT 6
+    #define COUNT 20
     // 168MHz STM32F405 STM32F407
 #elif (F_CPU == 168000000L)
-    #define COUNT 16
+    #define COUNT 40
 #elif (F_CPU == 80000000L)
-    #define COUNT 8
+    #define COUNT 22
 #elif (F_CPU == 160000000L)
-    #define COUNT 16
+    #define COUNT 32
 #else
     #define COUNT 24
     //#error "CPU SPEED NOT SUPPORTED"