initial commit

include/tca9548a.h

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <Wire.h>
+
+class Tca9548a {
+public:
+  explicit Tca9548a(uint8_t address) : address_(address), activeChannel_(0xFF) {}
+
+  bool begin() {
+    Wire.beginTransmission(address_);
+    return Wire.endTransmission() == 0;
+  }
+
+  bool selectChannel(uint8_t channel) {
+    if (channel > 7) {
+      return false;
+    }
+
+    const uint8_t mask = static_cast<uint8_t>(1u << channel);
+    if (mask == activeChannel_) {
+      return true;
+    }
+
+    Wire.beginTransmission(address_);
+    Wire.write(mask);
+    if (Wire.endTransmission() != 0) {
+      return false;
+    }
+
+    activeChannel_ = mask;
+    return true;
+  }
+
+  void disableAll() {
+    Wire.beginTransmission(address_);
+    Wire.write(0x00);
+    Wire.endTransmission();
+    activeChannel_ = 0x00;
+  }
+
+private:
+  uint8_t address_;
+  uint8_t activeChannel_;
+};