More debug messages when receiving a temperature

mqtt.lua

@@ -118,9 +118,10 @@ function registerMqtt()
         if (topic == (mqttPrefix .. "/cmd/single")) then
             handleSingleCommand(client, topic, data)
         elseif (topic == (mqttPrefix .. "/cmd/temp")) then
-	    if ( data == "" ) then
+	    if (( data == "" ) or (data == nil)) then
 		tw=nil
 	        tcol=nil
+		print("MQTT | wordclock failed")
 	    else
 		    -- generate the temperatur to display, once as it will not change
 		    local dispTemp = tonumber(data)
@@ -129,10 +130,10 @@ function registerMqtt()
 		    if (wc ~= nil) then
 			tw, tcol  = wc.temp(dw, rgbBuffer, invertRows)
 			wc = nil
+			print("MQTT | generated words for: " + tostring(dispTemp))
 		    else
 			print("MQTT | wordclock failed")
 		    end
-
 	    end
         else
             -- Handle here the /cmd/# sublevel