diff --git a/reactor-plc/startup.lua b/reactor-plc/startup.lua
index 2328a00..3905f0e 100644
--- a/reactor-plc/startup.lua
+++ b/reactor-plc/startup.lua
@@ -12,7 +12,7 @@ os.loadAPI("config.lua")
 os.loadAPI("plc.lua")
 os.loadAPI("threads.lua")
 
-local R_PLC_VERSION = "alpha-v0.4.12"
+local R_PLC_VERSION = "alpha-v0.4.13"
 
 local print = util.print
 local println = util.println
diff --git a/reactor-plc/threads.lua b/reactor-plc/threads.lua
index b1b331a..36d3179 100644
--- a/reactor-plc/threads.lua
+++ b/reactor-plc/threads.lua
@@ -483,7 +483,7 @@ function thread__setpoint_control(smem)
             end
 
             -- delay before next check
-            last_update = util.adaptive_delay(SETPOINT_CTRL_SLEEP, last_update)
+            last_update = util.adaptive_delay(SP_CTRL_SLEEP, last_update)
         end
     end