AN08 Cyclic traffic lights in Lua according to a defined table

Supported devices:  NETIO 4All, NETIO PowerPDU 4C, NETIO 4

In this Section 1, the Lua script described in this Application Note contains a user-defined table with 8 states that periodically turns on/off four 230V sockets (or 110/230V IEC-320 outlets in case of NETIO 4C). Each of these 8 states has a defined duration (5th number separated by a comma).

More states (table rows) can be added.

The action value for each output can 0, 1, 2, 3, 4 or 5. 

These values of 0 to 5 correspond to the values used in all M2M APIs of NETIO products. 

Actions 2 and 3 create a pulse of a defined width. For example, a state can last 5 seconds but it causes an output to be switched on for 2 seconds only (state2 in the example).

Action 5 is useful if the corresponding output is controlled by other means (button, mobile app, web interface). Action value 5 means that the output is unchanged. 

Creating the rule in Lua scripting language

To create and run the Lua script, do the following:

1) In the Actions section of NETIO 4 web administration, click Create Rule to add a rule

------------Section 1------------
local states = {"0000,1", --state1
                "3001,5", --state2
                "0010,1", --state3
                "1011,1", --state4
                "1100,1", --state5
                "0101,1", --state6
                "0110,1", --state7
                "0111,1"} --state8

local shortTimeMs = 1000 -- time used in states 2 and 3
---------End of Section 1---------

local currentState = 1 -- internal variable, do not change
local value -- internal variable
local time -- internal variable

local function checkFormat()
  for i=1,#states do
    local time = tonumber(states[i]:sub(6))
    if time == nil or time < -1 then
      logf("Time in state %d is invalid!",i)
      return false
    end
    local comma = states[i]:sub(5,5)
    if comma ~= "," then
      logf("Time in state %d is not separated by comma!", i)
      return false
    end
    for j=1,4 do
      local test = tonumber(states[i]:sub(j,j))
      if test == nil or test > 5 or test < 0 then
        logf("Value in state %d for outlet %d is invalid!", i,j)        
        return false
      end 
    end  
  end  
  return true
end

local function trafficLights()
  --logf("Current state: %d",currentState)
  time = tonumber(states[currentState]:sub(6))
  for i=1,4 do
    value = tonumber(states[currentState]:sub(i,i))
    if value == 0 then -- turn off
      devices.system.SetOut{output = i, value = false}
    elseif value == 1 then -- turn on
      devices.system.SetOut{output = i, value = true}
    elseif value == 2 then -- short off
      devices.system.SetOut{output = i, value = false}
      milliDelay(shortTimeMs,function() short(i,true) end)
    elseif value == 3 then -- short on
      devices.system.SetOut{output = i, value = true}
      milliDelay(shortTimeMs,function() short(i,false) end)   
    elseif value == 4 then -- toggle
      if devices.system["output" ..i.. "_state"] == 'on' then  
        devices.system.SetOut{output=i,value=false}
      else
        devices.system.SetOut{output=i, value=true}
      end
    elseif value == 5 then
      -- do nothing
    end
  end
  currentState = (currentState%#states) + 1
  delay(time,function() trafficLights() end)
end

local function short(outlet,state)
  devices.system.SetOut{output=outlet,value=state}
end

if checkFormat() then
  trafficLights()
end

In state 1, all outputs are switched off. After 30 seconds, the traffic lights transition to state 2 and output 4 is switched on. After another 30 seconds, output 3 is switched on, and so on, until all outputs are switched on in state 5. This state again lasts 30 seconds. Then, outputs are switched off one by one, starting with output 4. In state 8, only output 1 is on. From this state, the traffic lights transition back to state 1 and the cycle repeats.

In state 8, action 5 is used for one of the outputs. If the output has changed while the script was in the previous state, the output is not turned off. This is a difference from action 0.

Frequent issues

• Incorrect format
  • "0000" - time is not specified
  • "0000.30" - the actions and the time must be separated with a comma (,)
  • "0006,30" - allowed action values are 0 to 5
  • "000x,30" - to leave a socket unchanged, use 5
  •  0000,30  - double quotes missing

Starting the script

After configuring all the parameters and saving the script, the NETIO smart sockets need to be restarted. When the device boots again, the script is started and the outputs start to behave according to the table. If the script doesn’t start, please check the settings.

FAQ:

1) Is it possible to have a different number of states than 8?

Yes. Specify any number of desired states in the state variable. Pay attention to the correct format. Curly brackets are needed before the first state and after the last one, and individual states are comma-separated - as in the figures.

Examples for 4 states and 10 states:

This Application Note is compatible with:

	NETIO 4 NETIO 4 is smart power socket (smart power strip) with four 230V/8A sockets, connected to LAN and WiFi. Each of the four power sockets can be individually switched on/off using various M2M API protocols. NETIO 4 is a unique product designed for IT, industry, smart homes, multimedia installations and other applications. Use the product whenever you need 230V sockets controlled by a mobile app, by a computer program (via M2M API) or by a custom script (Lua), and featuring a timer (Scheduler) or auto reboot functionality (IP WatchDog).  More about NETIO 4
	NETIO 4All NETIO 4All is a PDU module featuring four 230V/8A power sockets with consumption metering for each socket as well as LAN and WiFi connectivity. Each of the four sockets can be individually switched on/off over the Web or using various M2M API protocols. Electricity consumption (A, W, kWh) can be measured at each power socket. NETIO 4All smart sockets are designed for remote measurement and control of electrical sockets. Use the product whenever you need 230V sockets controlled by a mobile app, by a computer program (via M2M API) or by a custom script (Lua) that runs directly in the NETIO 4All smart socket device. More about NETIO 4All
	NETIO PowerPDU 4C NETIO PowerPDU 4C is a small 110/230V PDU (Power Distribution Unit). Each of the four IEC-320 C13 outlets can be independently controlled (On / Off / Reset / Toggle). Electrical parameters (A, W, kWh, TPF, V, Hz) are measured with high accuracy at each outlet. The device features two LAN ports (and a built-in Ethernet switch) for connecting to a LAN. Each power output supports ZCS (Zero Current Switching) to protect the connected equipment. More about NETIO PowerPDU 4C