diff --git a/dmx/universe.cpp b/dmx/universe.cpp
index e4d4684..702389a 100644
--- a/dmx/universe.cpp
+++ b/dmx/universe.cpp
@@ -38,9 +38,10 @@ Universe::Universe() {
    @param uint16_t address of the requested slot.
    @return const uint8_t value of the slot.
 */
-const uint8_t Universe::slot (uint16_t address) const
+const uint8_t Universe::slot (const uint16_t address) const
 {
-    if (address > 512) return 0;
+    if (address == 0) return 0;
+    if (address > null_start_data_.size() - 1) return 0;
     return null_start_data_[address];
 }
 
@@ -63,6 +64,35 @@ void Universe::set(vector<uint8_t> vect) {
   }
 }
 
+/**
+  set value of a specific slot
+
+  @param uint16_t address of the slot being changed
+  @param uint8_t value being set
+*/
+void Universe::set(const uint16_t address, const uint8_t value)
+{
+    if (address == 0) return;
+    if (address > null_start_data_.size() - 1) return;
+    null_start_data_[address] = value;
+}
+
+/**
+  set value of a block of slots
+
+  @param uint16_t address of the slot being changed
+  @param uint16_t footprint of profile
+  @param uint8_t* values being set
+*/
+void Universe::set(const uint16_t start, const uint16_t footprint,
+                   const uint8_t* profile)
+{
+    if (start == 0) return;
+    if (start + footprint > null_start_data_.size() - 1) return;
+    for (int i = 0; i < footprint; i++)
+        null_start_data_[start + i] = profile[i];
+}
+
 /**
    register a data consumer callback function
 
diff --git a/dmx/universe.h b/dmx/universe.h
index 1b89777..20ffcec 100644
--- a/dmx/universe.h
+++ b/dmx/universe.h
@@ -60,9 +60,11 @@ class Universe {
     Universe ();
 
     const DimmerData * data() const { return &null_start_data_; }
-    const uint8_t slot (uint16_t address) const;
+    const uint8_t slot (const uint16_t) const;
 
     void set (vector<uint8_t>);
+    void set (const uint16_t, const uint8_t);
+    void set (const uint16_t, const uint16_t, const uint8_t*);
     void onData (const DataHandler);
 
   private: