ESP8266 Community Forum

- Sun Aug 06, 2017 10:03 am #68875 Hey!
I'm trying to get a wemos motor hat to work with Lua. (wemos D1 mini)

But gets this error when running the "test.lua" file and can not get what it is.
something is wrong with the line "motor1.speed(2000)"

**************************************************************************
test.lua:7: attempt to index global 'motor1' (a nil value)
stack traceback:
test.lua:7: in main chunk
[C]: in function 'dofile'
stdin:1: in main chunk
*****************************************************************************

test,lua:

Code: Select alldofile("motor-test.lua")

motor1 = Motor(0x00)
motor2 = Motor(0x01)


motor1.speed(2000)
--motor2.speed(-1000)

File "motortest.lua" (run by "test.lua")

Code: Select alllocal busid = 0
local scl = 2
local sda = 1
local dev_addr = 0x30

_STATE_BRAKE = 0x00
_STATE_RIGHT =0x01
_STATE_LEFT = 0x02
_STATE_STOP = 0x03
_STATE_SLEEP = 0x04

i2c.setup(busid, sda, scl, i2c.SLOW)


local Motor = {}
Motor.__index = Motor

print("1")

setmetatable(Motor, {
  __call = function (cls, ...)
    return cls.new(...)
  end,
  print("2")
})


function Motor.new(index)
    local self = setmetatable({}, Motor)
    self._index = index
    self._speed = 0
    self._state = 0
    self.frequency = 1000 --(1000 > 10000)
   
     print("Motor_new end" )

end

function Motor:__tostring()
    return "Motor  (" .. self._index .. ", " .. self._speed .. ", " .. self._state .. ")"
end
print("3")

function Motor:frequency(frequency)
    print("X")
    i2c.start(busid)
    i2c.address(busid, dev_addr, i2c.TRANSMITTER)
    print(self._index)
    i2c.write(busid, bit.bor(0x00, self._index), struct.pack('>BH', 0x00, frequency))
    i2c.stop(busid)
    print("motor-freq")
end

function Motor:update()
    i2c.start(busid)
    i2c.address(busid, dev_addr, i2c.TRANSMITTER)
    i2c.write(busid, bit.bor(0x10, self._index), struct.pack('>BH', self._state, self._speed))
    i2c.stop(busid)
    print("motor-update")
end

function Motor:speed(value)
    print("value=")
    if value>0 and value<=-10000 then
        self._speed = value
        self._state = _STATE_RIGHT
    elseif value<0 and value>=-10000 then
        self._speed = -1 * value
        self._state = _STATE_LEFT
    elseif value == 0 then
       self._speed = 0
        self._state = _STATE_STOP
    else
        print("Wrong Value")
    end
    print("Motor:speed")
    self.update()
end

function Motor:sleep()
    self._speed = 0
    self._state = _STATE_SLEEP
    self.update()
    print("Motor:sleep")
end

function Motor:brake()
    self._speed = 0
    self._state = _STATE_BRAKE
    self.update()
end   



- Sun Aug 06, 2017 4:24 pm #68890 Problem solved!
i did not hade the "struct" modul in my firmware...
but there vas also sum bugs ...

now i can run motor with different speed and directions.
but it need a little tuning of the code.