From cee62d02a0d92eb4c4f06901e53f68cb33d72c03 Mon Sep 17 00:00:00 2001
From: zeldan <zelei.dan@gmail.com>
Date: Thu, 24 Oct 2024 23:36:45 +0200
Subject: [PATCH] feat: handle negative values in calculations

---
 src/dht22.rs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/dht22.rs b/src/dht22.rs
index f704c1f..4455347 100644
--- a/src/dht22.rs
+++ b/src/dht22.rs
@@ -48,8 +48,14 @@ impl<P: InputPin + OutputPin, D: DelayNs> Dht22<P, D> {
         let humidity_value = ((humidity_high as u16) << 8) | (humidity_low as u16);
         let humidity_percentage = humidity_value as f32 / 10.0;
 
-        let temperature_value = ((temperature_high as u16) << 8) | (temperature_low as u16);
-        let temperatue_percentage = temperature_value as f32 / 10.0;
+        let temperature_high_clean = temperature_high & 0x7F; // 0x7F = 0111 1111
+        let temperature_value = ((temperature_high_clean as u16) << 8) | (temperature_low as u16);
+        let mut temperatue_percentage = temperature_value as f32 / 10.0;
+
+        if temperature_high & 0x80 != 0 {
+            temperatue_percentage = -temperatue_percentage;
+        }
+
 
         Ok(SensorReading {
             humidity: humidity_percentage,