Add i2c_read.cpp for TMP-1000 sensor integration

.github/workflows/ccpp.yml

@@ -2,10 +2,7 @@ name: C/C++ CI
 
 on:
   push:
-    # Sequence of patterns matched against refs/heads
-    branches:    
-      - master         # Push events on master branch
-      - '*'            # Matches all branch and tag names that don't contain a slash (/). 
+  workflow_dispatch:
 
 jobs:
   build_doodles:
@@ -14,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v7
     #- name: configure
     #  run: ./configure
     - name: make All doodles
@@ -31,16 +28,16 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v7
     #- name: configure
     #  run: ./configure
     - name: Build Encircular
       working-directory: ./Encircular
       run: make encircular
-    - name: Set up Python 3.7
-      uses: actions/setup-python@v1
+    - name: Set up Python
+      uses: actions/setup-python@v7
       with:
-        python-version: 3.7
+        python-version: 3.14
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
@@ -56,7 +53,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v7
     - name: build
       working-directory: ./inst
       run: make msg_parser
@@ -74,7 +71,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v7
     - name: build routing
       working-directory: ./EV-routing-challenge
       run: make solution
@@ -92,7 +89,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v7
     - name: cmake configure
       working-directory: ./
       run: cmake -S ./ -B build -DCMAKE_VERBOSE_MAKEFILE:BOOL=ON

doodles/Makefile

@@ -1,37 +1,41 @@
-all:	doodles ex2 ex3 memgoble file-search path array
+all:	doodles ex2 ex3 memgoble file-search path array undefined i2c_read
 .PHONY : all
 
 doodles:
 	@echo "Building $@: general assemblage of code tests"
-	g++ -lstdc++ -pthread -std=c++20 -o doodles src/doodles.cpp src/MapCheck.cpp
+	g++ -lstdc++ -pthread -std=c++23 -o doodles src/doodles.cpp src/MapCheck.cpp
 
 ex2:
 	@echo "Building $@: "
-	g++ -O3 -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o ex2 src/ex2.cpp
+	g++ -O3 -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o ex2 src/ex2.cpp
 
 ex3:
 	@echo "Building $@: "
-	g++ -O0 -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o ex3 src/ex3.cpp
+	g++ -O0 -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o ex3 src/ex3.cpp
 
 memgoble:
 	@echo "Building $@: application that continuously allocates memory"
-	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o memgoble src/memgoble.cpp
+	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o memgoble src/memgoble.cpp
 
 file-search:
 	@echo "Building $@: "
-	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o file-search src/file-search.cpp
+	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o file-search src/file-search.cpp
 
 path:
 	@echo "Building $@: "
-	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o obstacle-path src/obstacle-path.cpp
+	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o obstacle-path src/obstacle-path.cpp
 
 array:
 	@echo "Building $@: "
-	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o array_size src/array_size.cpp
+	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o array_size src/array_size.cpp
 
 undefined:
 	@echo "Building $@: "
-	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++20 -o undefined src/undefined.cpp
+	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o undefined src/undefined.cpp
+
+i2c_read:
+	@echo "Building $@: "
+	g++ -Wall -Wconversion -lstdc++ -pthread -std=c++23 -o undefined src/i2c_read.cpp
 
 clean:
 	rm -f *.o
@@ -40,6 +44,7 @@ clean:
 	rm -f ex3
 	rm -f doodles
 	rm -f file-search
+	rm -f i2c_read
 	rm -f obstacle-path
 	rm -f array_size
 	rm -f undefined

doodles/src/i2c_read.cpp

@@ -0,0 +1,161 @@
+/*
+ * ============================================================================
+ *  Embedded Coding Exercise — Rolling-Average Temperature Publisher (C++)
+ * ============================================================================
+ *
+ *  You are integrating the "TMP-1000" temperature sensor on a bare-metal MCU.
+ *
+ *  Sensor datasheet excerpt:
+ *    - Internal sample rate: 1000 Hz.
+ *    - Interface: I2C, 7-bit address 0x48.
+ *    - Register map (registers auto-increment during a burst read):
+ *        0x00  TEMP_MSB   upper 8 bits of the latest 16-bit sample
+ *        0x01  TEMP_LSB   lower 8 bits
+ *      The sample is a signed 16-bit two's-complement value.
+ *      A single 2-byte burst read starting at 0x00 returns one coherent
+ *      sample. Two separate 1-byte reads are NOT guaranteed to come from
+ *      the same sample. Reading TEMP_LSB clears the data-ready condition.
+ *    - Scale: 1 LSB = 0.03125 degC  (degC = raw / 32.0).
+ *    - Valid operating range: -50 degC to +750 degC. Values outside this
+ *      range indicate a sensor fault.
+ *    - DRDY: the sensor drives PIN2 high (rising edge) each time a new
+ *      sample becomes available.
+ *
+ *  Task:
+ *    Publish, at 10 Hz over the UART, the rolling average of the sensor
+ *    samples from the last 250 ms, as an ASCII line such as:
+ *        "T=23.41\n"
+ *    The publish rate must not drift over time.
+ *
+ *  Notes:
+ *    - Target is a small MCU: be deliberate about memory, ISR duration,
+ *      and what runs in interrupt vs. main context.
+ *    - You may use the standard library.
+ *    - State any assumptions you make about the HAL semantics.
+ *    - Think out loud about edge cases; handling or explicitly documenting
+ *      them counts.
+ *
+ * ============================================================================
+ *  Provided HAL (already implemented — do not modify, just use it)
+ * ============================================================================
+ */
+#include <cstdint>
+#include <cstddef>
+
+#include <queue>
+#include <atomic>
+
+
+enum PinName { PIN2, I2C_SDA, I2C_SCL, USBTX, USBRX };
+
+// Monotonic millisecond tick since boot. Wraps around at 2^32.
+uint32_t millis();
+
+// Globally disable / enable interrupts (for critical sections).
+void __disable_irq();
+void __enable_irq();
+
+class I2C {
+public:
+  	const int TEMP_MSB{0x0};
+  	const int TEMP_LSB{0x1};
+  	const float conversion_scale{32.0};
+
+    I2C(PinName sda, PinName scl);
+
+  	bool Init() {      
+      return true;
+    }
+    // Both return 0 on success, non-zero on NACK / bus error.
+    // repeated=true ends the transfer without a STOP so the next
+    // transfer begins with a repeated START.
+    int write(int address_7bit, const char* data, int length, bool repeated = false);
+    int read(int address_7bit, char* data, int length, bool repeated = false);
+
+  	float GetAvg();
+  	// To be called in the intterupt handler
+    void read_data() {
+    	// TODO: handle failures
+
+      uint16_t raw_data{0};
+      {
+      	char data{0};
+      	const auto res = read(TEMP_MSB, &data, 1, false);      
+        raw_data = (static_cast<uint16_t>(data) << 8);
+      }
+      {
+      	char data{0};
+      	const auto res = read(TEMP_MSB, &data, 1, false);      
+        raw_data = (raw_data & static_cast<uint16_t>(data));
+      }
+
+      // convert to float
+      const float real_data = static_cast<float)(raw_data) / conversion_scale;
+
+      // TODO: make sure the API doesn't allocate.
+      // avg = (x1 + x2 + ... xn) / n
+      // avg+1 = ((avg * n) + xn+1) / n+1
+      // 
+      if (data_.full()) {
+        data_.pop_front();
+      }
+      data_.push_back(real_data);
+  	}
+
+private:
+  std::atomic<float> avg_data_{0.0f};
+};
+
+class Serial {
+public:
+    Serial(PinName tx, PinName rx, int baud = 115200);
+    // Blocking write; returns bytes written or negative on error.
+    long write(const void* buffer, size_t length);
+};
+
+class InterruptIn {
+public:
+    explicit InterruptIn(PinName pin, std::function<void ()> callback) : pin_(pin), callback_(callback) {};
+    void rise(void (*callback)());   // callback runs in interrupt context
+    void enable_irq();
+    void disable_irq();
+
+private:
+  std::atomic<uint16_t> raw_temperature_{};
+  std::function<> callback_;
+  const PinName pin_;
+};
+
+/*
+ * ============================================================================
+ *  Your implementation starts here.
+ * ============================================================================
+ */
+
+int main() {
+    I2C i2c(I2C_SDA, I2C_SCL);
+  	if (i2c.Init() == false) {
+      return 1;
+    }
+
+    Serial serial(USBTX, USBRX);
+
+  	// TODO: check the function pointer syntax
+    InterruptIn drdy(PIN2, i2c.read_data());
+  	drdy.enable_irq();
+
+    // TODO: implement.
+  	// Interrupt on PIN2 when data is ready.
+  	// Read the data, put in the queue.
+  	// Write at 10Hz.
+
+  	std::string uart_buffer{132};
+
+    for (;;) {
+        // TODO
+      	// read mills();
+      	// If mod 100ms - use std::format() to format into uart_buffer, then serial.write(uart_buffer.data(), uart_buffer.size())
+    }
+
+  	return 0;
+}