From 7844c8bdce40aaab7a18ddddc7007cac3282028b Mon Sep 17 00:00:00 2001
From: hasslesstech <hasslesstech@tutanota.com>
Date: Sat, 19 Apr 2025 13:38:11 +0300
Subject: [PATCH] [DHT11] minor bugfixes, minor speed improvements

- fix timeout awaiting, add more time
- move SKIP_LOW into dht11_measure_high_duration function to execute the function call before the PD11 line goes high, thus increasing the precision of signal length measurement
---
 .cproject        |  2 +-
 Core/Src/DHT11.c | 12 ++++++------
 Core/Src/main.c  | 17 ++++++++++++-----
 test1.ioc        |  2 ++
 4 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/.cproject b/.cproject
index 29ae4a7..d1f618c 100644
--- a/.cproject
+++ b/.cproject
@@ -36,7 +36,7 @@
 							</tool>
 							<tool id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.1285639549" name="MCU/MPU GCC Compiler" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler">
 								<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.debuglevel.75005491" name="Debug level" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.debuglevel" useByScannerDiscovery="false" value="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.debuglevel.value.g3" valueType="enumerated"/>
-								<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.optimization.level.1711938240" name="Optimization level" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.optimization.level" useByScannerDiscovery="false"/>
+								<option id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.optimization.level.1711938240" name="Optimization level" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.optimization.level" useByScannerDiscovery="false" value="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.optimization.level.value.o0" valueType="enumerated"/>
 								<option IS_BUILTIN_EMPTY="false" IS_VALUE_EMPTY="false" id="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.definedsymbols.1662015804" name="Define symbols (-D)" superClass="com.st.stm32cube.ide.mcu.gnu.managedbuild.tool.c.compiler.option.definedsymbols" useByScannerDiscovery="false" valueType="definedSymbols">
 									<listOptionValue builtIn="false" value="DEBUG"/>
 									<listOptionValue builtIn="false" value="USE_HAL_DRIVER"/>
diff --git a/Core/Src/DHT11.c b/Core/Src/DHT11.c
index 820f10a..a40e155 100644
--- a/Core/Src/DHT11.c
+++ b/Core/Src/DHT11.c
@@ -15,6 +15,7 @@ static void wait(uint32_t wait_us)
 
 static size_t dht11_measure_high_duration(void)
 {
+	SKIP_LOW;
 	uint32_t start_time = TIM2->CNT;
 	SKIP_HIGH;
 	uint32_t end_time = TIM2->CNT;
@@ -28,7 +29,7 @@ static size_t dht11_read_value(struct DHT11_Data *data)
 	// treat data as a normal array to simplify read loop
 	uint8_t *buffer = (uint8_t *) data;
 
-	register uint8_t read_register = 0;
+	register uint32_t read_register = 0;
 
 	TIM2->CNT = 0;
 	HAL_TIM_Base_Start(&htim2);
@@ -44,11 +45,11 @@ static size_t dht11_read_value(struct DHT11_Data *data)
 
 	GPIOD->MODER &= 0xFF3FFFFF;      // switch GPIOD 11 to input mode
 
-	// reading transmission from DHT11
+	// reading pull down from DHT11
 	SKIP_LOW;
 
-	// waiting for 50 ms max
-	for (size_t i = TIM2->CNT + (50000 << 4); TIM2->CNT >= i; )
+	// waiting for 500ms max
+	for (size_t i = TIM2->CNT + (500000 << 4); TIM2->CNT <= i; )
 		if (!(GPIOD->IDR & 0x0800))
 			goto reading_data;
 
@@ -60,11 +61,10 @@ reading_data:
 	for (size_t i = 0; i < 5; i++) {
 		for (register size_t j = 0; j < 8; j++) {
 			read_register <<= 1;
-			SKIP_LOW;
 			read_register |= dht11_measure_high_duration();
 		}
 
-		buffer[i] = read_register;
+		buffer[i] = (uint8_t) read_register;
 	}
 
 	HAL_TIM_Base_Stop(&htim2);
diff --git a/Core/Src/main.c b/Core/Src/main.c
index 0ed7e52..ec57b4e 100644
--- a/Core/Src/main.c
+++ b/Core/Src/main.c
@@ -112,7 +112,7 @@ int delay_between_runs[] = {
 		-1
 		};
 
-size_t current_executor_id = 0;
+size_t current_executor_id = 11;
 
 size_t buttons_interrupt_enabled;
 
@@ -641,10 +641,17 @@ static void MX_GPIO_Init(void)
   GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
   HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
 
-  /*Configure GPIO pins : PD11 PD12 PD13 PD14
-                           PD15 PD4 PD7 */
-  GPIO_InitStruct.Pin = GPIO_PIN_11|GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14
-                          |GPIO_PIN_15|GPIO_PIN_4|GPIO_PIN_7;
+  /*Configure GPIO pin : PD11 */
+  GPIO_InitStruct.Pin = GPIO_PIN_11;
+  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
+  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
+
+  /*Configure GPIO pins : PD12 PD13 PD14 PD15
+                           PD4 PD7 */
+  GPIO_InitStruct.Pin = GPIO_PIN_12|GPIO_PIN_13|GPIO_PIN_14|GPIO_PIN_15
+                          |GPIO_PIN_4|GPIO_PIN_7;
   GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
   GPIO_InitStruct.Pull = GPIO_NOPULL;
   GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
diff --git a/test1.ioc b/test1.ioc
index 6d4604d..571959d 100644
--- a/test1.ioc
+++ b/test1.ioc
@@ -121,6 +121,8 @@ PC8.Locked=true
 PC8.Signal=GPIO_Input
 PC9.Locked=true
 PC9.Signal=GPIO_Input
+PD11.GPIOParameters=GPIO_Speed
+PD11.GPIO_Speed=GPIO_SPEED_FREQ_VERY_HIGH
 PD11.Locked=true
 PD11.Signal=GPIO_Output
 PD12.Locked=true