diff --git a/de_react_auto b/de_react_auto
index 8cf8e0e..22982fd 100644
--- a/de_react_auto
+++ b/de_react_auto
@@ -533,16 +533,21 @@ local function controlReactor()
 
     elseif state == STATES.CHARGING then
         -- CHARGING: High field input to charge up
-        -- SAFETY: Prevent division by zero
-        local maxField = reactorInfo.maxFieldStrength or 1
-        if maxField <= 0 then maxField = 1 end
+        local maxField = reactorInfo.maxFieldStrength or 0
 
-        local fieldStrength = (reactorInfo.fieldStrength or 0) / maxField
-        local chargeNeeded = CONFIG.charge_field_target - fieldStrength
+        if maxField > 0 then
+            -- Reactor has valid maxFieldStrength - calculate based on charge needed
+            local fieldStrength = (reactorInfo.fieldStrength or 0) / maxField
+            local chargeNeeded = CONFIG.charge_field_target - fieldStrength
 
-        -- Charge faster when further from target
-        inputRate = math.floor(maxField * math.max(0.1, chargeNeeded))
-        inputRate = math.max(inputRate, calculateFieldInput())
+            -- Charge faster when further from target
+            inputRate = math.floor(maxField * math.max(0.1, chargeNeeded))
+            inputRate = math.max(inputRate, calculateFieldInput())
+        else
+            -- Reactor is cold/initializing - use emergency input to charge field
+            -- This provides enough power to establish the containment field
+            inputRate = CONFIG.emergency_field_input
+        end
         outputRate = 0
 
     elseif state == STATES.WARMING_UP then
@@ -862,7 +867,7 @@ local function updateDisplay()
     -- Instructions
     mon.setCursorPos(1, y)
     mon.setTextColor(colors.gray)
-    mon.write("Press Q to shutdown, R to restart")
+    mon.write("Press Q to shutdown, C to charge")
 end
 
 -- ============================================================================
@@ -877,8 +882,8 @@ local function handleInput()
             -- Request shutdown
             shutdownRequested = true
             print("Shutdown requested...")
-        elseif key == keys.r then
-            -- Restart reactor
+        elseif key == keys.c then
+            -- Charge reactor
             if state == STATES.OFFLINE or state == STATES.SHUTDOWN then
                 shutdownRequested = false
                 if reactor then
@@ -1068,7 +1073,7 @@ local function main()
 
     print("Starting control loop...")
     print("Press Q to shutdown reactor")
-    print("Press R to restart reactor")
+    print("Press C to charge reactor")
     print("Press X to exit program")
     print("")
     print("!!! IMPORTANT: If this program stops unexpectedly,")