ES ordening

ES/ES assignment 4/ES assignment 3 I2C/assignment-C/Master.cpp

@@ -0,0 +1,60 @@
+#include <Arduino.h>
+#include <Wire.h>
+
+#define DEVICE_ADDRESS 0x50
+
+// Virtual hardware registers
+uint8_t reg_INA = 0;
+uint8_t reg_INB = 0;
+uint8_t reg_pointer = 0;  // acts as address register for reads
+
+
+
+// Called when master writes data
+void receiveEvent(int howMany) {
+  if (howMany < 1) return;
+
+  // First byte is always register address
+  reg_pointer = Wire.read();
+  howMany--;
+
+  if (howMany == 1) {
+    // Second byte is data to write
+    uint8_t value = Wire.read();
+    if (reg_pointer == 0x21) {
+      reg_INA = value;
+      Serial.println("INA set");
+    } else if (reg_pointer == 0x22) {
+      reg_INB = value;
+      Serial.println("INB set");
+    } else {
+      // Writes to read-only registers are ignored
+      Serial.println("Write to read-only register ignored");
+    }
+  }
+}
+
+// Called when master reads data
+void requestEvent() {
+  uint8_t value = 0;
+
+  switch (reg_pointer) {
+    case 0x21: value = reg_INA; break;
+    case 0x22: value = reg_INB; break;
+    case 0x23: value = min(reg_INA, reg_INB); break;
+    case 0x24: value = max(reg_INA, reg_INB); break;
+    default: value = 0xFF; break; // undefined register
+  }
+
+  Wire.write(value);
+}
+
+void setup() {
+  Wire.begin(DEVICE_ADDRESS);
+  Wire.onReceive(receiveEvent);
+  Wire.onRequest(requestEvent);
+  Serial.begin(9600);
+}
+
+void loop() {
+}