diff --git a/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/DigitalInputRTU.cpp b/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/DigitalInputRTU.cpp
new file mode 100644
index 0000000..61c71f4
--- /dev/null
+++ b/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/DigitalInputRTU.cpp
@@ -0,0 +1,83 @@
+#include <DigitalInputRTU.hpp>
+
+DigitalInputRTU::DigitalInputRTU()
+{
+    this->iot = nullptr;
+    this->size = 0;
+    this->callbackCount = 0;
+    for (int i = 0; i < 16; i++)
+        this->inputBuffer[i] = false;
+}
+
+DigitalInputRTU::~DigitalInputRTU()
+{
+
+}
+
+void DigitalInputRTU::begin(char *remoteBaseTopic, uint8_t remote_card_slot, ESPMegaIoT *iot)
+{
+    this->remoteBaseTopic = remoteBaseTopic;
+    this->remoteBaseTopicLength = strlen(remoteBaseTopic);
+    this->cardSlot = remote_card_slot;
+    this->iot = iot;
+}
+
+void DigitalInputRTU::subscribe()
+{
+    // Subscribe to all pins
+    for(uint8_t i = 0; i < 16; i++)
+    {
+        char* topic = (char*)calloc(this->remoteBaseTopicLength + 6, sizeof(char));
+        sprintf(topic, "%s/%02d/%02d", this->remoteBaseTopic, this->cardSlot, i);
+        this->iot->subscribe(topic);
+        free(topic);
+    }
+}
+
+bool DigitalInputRTU::digitalRead(uint8_t pin)
+{
+    return this->inputBuffer[pin];
+}
+
+uint8_t DigitalInputRTU::registerCallback(std::function<void(uint8_t, bool)> callback)
+{
+    this->callbacks[callbackCount] = callback;
+    return callbackCount++;
+}
+
+void DigitalInputRTU::unregisterCallback(uint8_t handler)
+{
+    this->callbacks.erase(handler);
+}
+
+void DigitalInputRTU::mqttCallback(char *topic, char *payload)
+{
+    // First trim base topic from topic
+    char* topicWithoutBase = topic + this->remoteBaseTopicLength;
+    // Then check if topic is in format /cardSlot/pin
+    // Example trimmed topic: /01/00
+    // Card slot range from 00 to 99
+    // Pin range from 00 to 15
+    // Note that both card and pin are padded with 0 if they are less than 10
+    if(strlen(topicWithoutBase) != 6)
+        return;
+    if(topicWithoutBase[0] != '/')
+        return;
+    if(topicWithoutBase[3] != '/')
+        return;
+    // Extract card slot and pin
+    uint8_t cardSlot = (topicWithoutBase[1] - '0') * 10 + (topicWithoutBase[2] - '0');
+    uint8_t pin = (topicWithoutBase[4] - '0') * 10 + (topicWithoutBase[5] - '0');
+    // Check if card slot is correct
+    if(cardSlot != this->cardSlot)
+        return;
+    // Extract value
+    bool value = strcmp(payload, "1") == 0;
+    // Update input buffer
+    this->inputBuffer[pin] = value;
+    // Call callbacks
+    for(auto const& callback : this->callbacks)
+    {
+        callback.second(pin, value);
+    }
+}
diff --git a/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/DigitalInputRTU.hpp b/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/DigitalInputRTU.hpp
new file mode 100644
index 0000000..b421241
--- /dev/null
+++ b/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/DigitalInputRTU.hpp
@@ -0,0 +1,20 @@
+#pragma once
+#include <ESPMegaRTU.hpp>
+
+class DigitalInputRTU : public ESPMegaRTU {
+    public:
+        DigitalInputRTU();
+        ~DigitalInputRTU();
+        void begin(char* remoteBaseTopic, uint8_t remote_card_slot, ESPMegaIoT* iot);
+        void subscribe();
+        bool digitalRead(uint8_t pin);
+        uint8_t registerCallback(std::function<void(uint8_t, bool)> callback);
+        void unregisterCallback(uint8_t handler);
+    private:
+        void mqttCallback(char* topic, char* payload);
+        ESPMegaIoT* iot;
+        size_t size;
+        uint16_t callbackCount;
+        std::map<uint8_t, std::function<void(uint8_t, bool)>> callbacks;
+        bool inputBuffer[16];
+};
\ No newline at end of file
diff --git a/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/ESPMegaRTU.hpp b/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/ESPMegaRTU.hpp
new file mode 100644
index 0000000..aa42ea4
--- /dev/null
+++ b/ESPMegaPRO-OS-SDK/lib/ESPMegaPRO/ESPMegaRTU.hpp
@@ -0,0 +1,15 @@
+#pragma once
+#include <ESPMegaIoT.hpp>
+
+class ESPMegaRTU {
+    public:
+        ESPMegaRTU();
+        ~ESPMegaRTU();
+        virtual void subscribe();
+        virtual void begin(char* remote_base_topic, uint8_t remote_card_slot, ESPMegaIoT* iot);
+    protected:
+        char* remoteBaseTopic;
+        uint8_t remoteBaseTopicLength;
+        uint8_t cardSlot;
+        ESPMegaIoT* iot;
+};
\ No newline at end of file