diff --git a/station_2_4_2.lua b/station_2_4_2.lua
new file mode 100644
index 0000000..5e9e219
--- /dev/null
+++ b/station_2_4_2.lua
@@ -0,0 +1,395 @@
+--[[
+    Station 2/4 Standard Schedule Program
+]]
+
+require("libevent")
+require("util")
+require("checkarg")
+require("queue")
+local sides=require("sides")
+
+-- Config your update functions here (Do not change function name)
+local redin1 = proxy("redstone", "")
+local redin2 = proxy("redstone", "")
+local redin3 = proxy("redstone", "")
+local redout1 = proxy("redstone", "")
+local redout2 = proxy("redstone", "")
+
+-- Redirect Table
+local redirect_tb=
+{
+    ["ab_st"]={redin1,sides.north},
+    ["ab_sr"]={redin1,sides.east},
+    ["ab_lout"]={redin1,sides.south},
+
+    ["ba_st"] = {redin2,sides.north},
+    ["ba_sr"] = {redin2,sides.east},
+    ["ba_lout"] = {redin2,sides.south},
+
+    -- ins: Inside station sensor
+    ["ab_ins1"] = {redin3,sides.north},
+    ["ab_ins2"] = {redin3,sides.east},
+    ["ba_ins1"] = {redin3,sides.south},
+    ["ba_ins2"] = {redin3,sides.west},
+
+    ["ab_ko"]={redout1,sides.north},
+    ["ab_m"]={redout1,sides.east},
+    ["ab_k1"]={redout1,sides.south},
+    ["ab_k2"]={redout1,sides.west},
+
+    ["ba_ko"]={redout2,sides.north},
+    ["ba_m"]={redout2,sides.east},
+    ["ba_k1"]={redout2,sides.south},
+    ["ba_k2"]={redout2,sides.west},
+
+    ["last_unused"]={"unused",sides.north}
+}
+
+local function getNameFromRaw(Device,Side)
+    for k,t in pairs(redirect_tb) do 
+        if(t[1].address == Device and t[2]==Side) then 
+            return k
+        end
+    end
+
+    return nil
+end
+
+local function getRawFromName(Name)
+    return redirect_tb[Name][1],redirect_tb[Name][2]
+end
+
+local function enabledevice(Name)
+    local d, s = getRawFromName(Name)
+    if (d ~= nil and s ~= nil) then
+        d.setOutput(s, 15)
+    end
+end
+
+local function disabledevice(Name)
+    local d, s = getRawFromName(Name)
+    if (d ~= nil and s ~= nil) then
+        d.setOutput(s, 0)
+    end
+end
+
+local function readdevice(Name)
+    local d,s=getRawFromName(Name)
+    if(d~=nil and s~=nil) then
+        return d.getInput(s)
+    else
+        -- Critical error
+        error("failed to read device input")
+    end
+end
+
+local evl=Queue.new()
+
+local function train_delegator(Name,callback_func)
+    local ret=AddEventListener("redstone_changed",
+        function(ev,dev,sd,from,to)
+            if(getNameFromRaw(dev,sd)==Name) then
+                callback_func(from,to)
+            end
+        end)
+    evl:push(ret)
+end
+
+local ab_available_1=true
+local ab_available_2=true
+local ab_timerid_1,ab_time_1=0,0
+local ab_timerid_2,ab_time_2=0,0
+local ab_timerid_out,ab_time_out=0,0
+
+local ba_available_1=true
+local ba_available_2=true
+local ba_timerid_1,ba_time_1=0,0
+local ba_timerid_2,ba_time_2=0,0
+local ba_timerid_out,ba_time_out=0,0
+
+local ebus=Queue.new()
+
+local function doCheck()
+    if(redin1==nil or redin2==nil or redin3==nil or redout1==nil or redout2==nil) then
+        error("Check Failed. Please review your redstone configure")
+    end
+end
+
+local function doInit()
+    evl:push(AddEventListener("interrupted",
+        function()
+            ebus:push("stop")
+        end))
+
+    --- AB
+    train_delegator("ab_st",
+        function(from,to)
+            if(from<to) then
+                ebus:push("ab_new_train")
+            else 
+                ebus:push("ab_train_in")
+            end
+        end
+    )
+    train_delegator("ab_ins1",
+        function(from,to)
+            if(from<to) then
+                ebus:push("ab_ins1_ready")
+            else
+                ebus:push("ab_ins1_leave")
+            end
+        end
+    )
+    train_delegator("ab_ins2",
+        function(from,to)
+            if(from<to) then
+                ebus:push("ab_ins2_ready")
+            else
+                ebus:push("ab_ins2_leave")
+            end
+        end
+    )
+
+    --- BA
+    train_delegator("ba_st",
+        function(from,to)
+            if(from<to) then
+                ebus:push("ba_new_train")
+            else 
+                ebus:push("ba_train_in")
+            end
+        end
+    )
+    train_delegator("ba_ins1",
+        function(from,to)
+            if(from<to) then
+                ebus:push("ba_ins1_ready")
+            else
+                ebus:push("ba_ins1_leave")
+            end
+        end
+    )
+    train_delegator("ba_ins2",
+        function(from,to)
+            if(from<to) then
+                ebus:push("ba_ins2_ready")
+            else
+                ebus:push("ba_ins2_leave")
+            end
+        end
+    )
+end
+
+local function doCleanUp()
+    while(evl:top()~=nil) do
+        RemoveEventListener(evl:pop())
+    end
+end
+
+local function doClearOutput()
+    disabledevice("ab_ko")
+    disabledevice("ab_m")
+    disabledevice("ab_k1")
+    disabledevice("ab_k2")
+    disabledevice("ba_ko")
+    disabledevice("ba_m")
+    disabledevice("ba_k1")
+    disabledevice("ba_k2")
+end
+
+local function TCSMain()
+    doCheck()
+    doClearOutput()
+    doInit()
+    print("TCS Started. Press Ctrl+C to stop.")
+    -- Main Processing Loop
+    local running=true
+    while(running) do
+        os.sleep(0.5)
+        
+        local ev="no_event"
+        if(ebus:top()~=nil) then
+            ev=ebus:pop() -- Notice: Event is already poped.
+        end
+        
+        -- For Debug: Print Event Name
+        if(ev~="no_event") then
+            print(ev)
+        end
+
+        if(ev=="no_event") then
+            -- No event, no action.
+        elseif(ev=="stop") then
+            running=false
+        --- AB
+        elseif(ev=="ab_new_train") then -- AB New Train
+            local act=false
+            if(readdevice("ab_sr")>0) then -- This train will coming into station
+                if(ab_available_1) then 
+                    ab_available_1=false
+                    act=true
+                    ab_time_1=0
+                    ab_timerid_1=AddTimer(1,
+                        function()
+                            ab_time_1=ab_time_1+1
+                        end,
+                        -1)
+                    disabledevice("ab_m")
+                    disabledevice("ab_k1")
+                end
+            else -- This train will pass by station
+                if(ab_available_2) then 
+                    ab_available_2=false
+                    act=true
+                    ab_time_2=0
+                    ab_timerid_2=AddTimer(1,
+                        function()
+                            ab_time_2=ab_time_2+1
+                        end,
+                        -1)
+                    enabledevice("ab_m")
+                    disabledevice("ab_k2")
+                end
+            end
+
+            if(act) then
+                enabledevice("ab_ko")
+                os.sleep(0.25)
+                disabledevice("ab_ko")
+            else -- Push Event back
+                ebus:push(ev)
+            end
+        elseif(ev=="ab_ins1_ready") then
+            if(ab_time_out==0 and ab_time_1>6 and ab_time_1>ab_time_2 and readdevice("ab_lout")>0) then
+                RemoveTimer(ab_timerid_1)
+                ab_time_1=0
+                ab_available_1=true
+                
+                ab_time_out=1
+                ab_timerid_out=AddTimer(1,
+                    function()
+                        ab_time_out=ab_time_out+1
+                        if(ab_time_out==5) then
+                            ebus:push("ab_time_out_needstop")
+                        end
+                    end,-1)
+                
+                enabledevice("ab_k1")
+            else
+                ebus:push(ev)
+            end
+        elseif(ev=="ab_ins2_ready") then
+            if(ab_time_out==0 and ab_time_2>ab_time_1 and readdevice("ab_lout")>0) then
+                RemoveTimer(ab_timerid_2)
+                ab_time_2=0
+                ab_available_2=true
+                
+                ab_time_out=1
+                ab_timerid_out=AddTimer(1,
+                    function()
+                        ab_time_out=ab_time_out+1
+                        if(ab_time_out==5) then
+                            ebus:push("ab_time_out_needstop")
+                        end
+                    end,-1)
+                
+                enabledevice("ab_k2")
+            else
+                ebus:push(ev)
+            end
+        --- BA
+        elseif(ev=="ba_new_train") then -- AB New Train
+            local act=false
+            if(readdevice("ba_sr")>0) then -- This train will coming into station
+                if(ba_available_1) then 
+                    ba_available_1=false
+                    act=true
+                    ba_time_1=0
+                    ba_timerid_1=AddTimer(1,
+                        function()
+                            ba_time_1=ba_time_1+1
+                        end,
+                        -1)
+                    disabledevice("ba_m")
+                    disabledevice("ba_k1")
+                end
+            else -- This train will pass by station
+                if(ba_available_2) then 
+                    ba_available_2=false
+                    act=true
+                    ba_time_2=0
+                    ba_timerid_2=AddTimer(1,
+                        function()
+                            ba_time_2=ba_time_2+1
+                        end,
+                        -1)
+                    enabledevice("ba_m")
+                    disabledevice("ba_k2")
+                end
+            end
+
+            if(act) then
+                enabledevice("ba_ko")
+                os.sleep(0.25)
+                disabledevice("ba_ko")
+            else -- Push Event back
+                ebus:push(ev)
+            end
+        elseif(ev=="ba_ins1_ready") then
+            if(ba_time_out==0 and ba_time_1>6 and ba_time_1>ba_time_2 and readdevice("ba_lout")>0) then
+                RemoveTimer(ba_timerid_1)
+                ba_time_1=0
+                ba_available_1=true
+                
+                ba_time_out=1
+                ba_timerid_out=AddTimer(1,
+                    function()
+                        ba_time_out=ba_time_out+1
+                        if(ba_time_out==5) then
+                            ebus:push("ba_time_out_needstop")
+                        end
+                    end,-1)
+                
+                enabledevice("ba_k1")
+            else
+                ebus:push(ev)
+            end
+        elseif(ev=="ba_ins2_ready") then
+            if(ba_time_out==0 and ba_time_2>ba_time_1 and readdevice("ba_lout")>0) then
+                RemoveTimer(ba_timerid_2)
+                ba_time_2=0
+                ba_available_2=true
+                
+                ba_time_out=1
+                ba_timerid_out=AddTimer(1,
+                    function()
+                        ba_time_out=ba_time_out+1
+                        if(ba_time_out==5) then
+                            ebus:push("ba_time_out_needstop")
+                        end
+                    end,-1)
+                
+                enabledevice("ba_k2")
+            else
+                ebus:push(ev)
+            end
+        elseif(ev=="ab_time_out_needstop") then
+            RemoveTimer(ab_timerid_out)
+            ab_time_out=0
+        elseif(ev=="ba_time_out_needstop") then 
+            RemoveTimer(ba_timerid_out)
+            ba_time_out=0
+        else -- Ignore unknown event
+            -- Do nothing
+        end
+
+    end
+
+    doCleanUp()
+    doClearOutput()
+end
+
+-- Start-up script
+print("Program Start")
+TCSMain()
+print("Program Stop")