-- M5450.lua  John Longworth June 2017
-- Use ESP8266 to drive the M5450 IC

clock = 1 -- Change these to whatever pins you are using
data = 2
buffer = {}
a = {0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1}

gpio.mode(clock,gpio.OUTPUT)  -- Set pins to outputs
gpio.mode(data,gpio.OUTPUT)

function writeBits()  -- Write buffer to to M5450
    buffer[35] = 1  -- needs to be 1
    buffer[36] = 0  -- extra element to stop array going beyond its bounds
    for i = 0, 35 do
        gpio.write(clock,gpio.HIGH)             
        gpio.write(data,buffer[i])    
        gpio.write(clock,gpio.LOW)
    end
    i = nil
end   

function init()  -- Make buffer
    for i = 0, 36 do
        buffer[i] = 0
    end  
    i = nil      
    writeBits()    
end  

function random()  -- Set random LEDs on or off
    tmr.alarm(0,1000,1,function()
        for i = 0, 34 do
            buffer[i] = node.random(0,1)            
        end
        i = nil
        writeBits()        
    end)
end    

function chaser()  -- 3 LED Chaser
    tmr.alarm(0,50,1,function()
        for i = 0, 34 do
            buffer[i] = 0
        end         
        i = nil
        count = count + 1
        buffer[count - 1] = 1  
        buffer[count] = 1
        buffer[count + 1] = 1             
        if count > 34 then 
            count = 1 
        end
        i = nil     
        writeBits()               
    end)
end   

function allOnOff()  -- Turn all LEDs on and off
    tmr.alarm(0,500,1,function()
        for i = 0, 34 do
            buffer[i] = 1
        end 
        writeBits()
        i = nil     
    end)
    tmr.alarm(1,1000,1,function()
        for i = 0, 34 do
            buffer[i] = 0
        end  
        writeBits()
        i = nil   
    end)
end

function arrayFill() -- Use an array of pre defined values to set LEDS on or off
    for i = 0, 34 do
        buffer[i-1] = a[i]        
    end     
    writeBits()
    i = nil     
end

function stop()
    tmr.stop(0)
    tmr.stop(1)
    arrayFill()    
end

init()
random()
count = 1
tmr.alarm(2,10000,0,chaser)
tmr.alarm(3,20000,0,allOnOff)
tmr.alarm(4,30000,0,stop)