- Mon Apr 06, 2015 4:06 pm
#13675
Hi there, I didn't find any stepper driver so I throw something simple together and it did seem to work.
This is my first try writing lua-code so it is probably not that great, but I thought I'll share it anyway...
I was testing it with a l293d ic and a stepper from ebay, 5v from usb charger to the l293d, data from gpio on esp-12, LM1117-3.3 for esp power. Other connections just as in http://www.instructables.com/id/Getting ... 66-ESP-12/
Here is the little code snippet...
transfer the file as stepper.lua and run it with
This is my first try writing lua-code so it is probably not that great, but I thought I'll share it anyway...
I was testing it with a l293d ic and a stepper from ebay, 5v from usb charger to the l293d, data from gpio on esp-12, LM1117-3.3 for esp power. Other connections just as in http://www.instructables.com/id/Getting ... 66-ESP-12/
Here is the little code snippet...
Code: Select all
-- stepper.lua
-- simple stepper driver for controlling a stepper motor with a
-- l293d driver
-- esp-12 pins: 16 14 12 13
-- nodemcu pins: 0 5 6 7
stepper_pins = {0,5,6,7}
-- half or full stepping
step_states4 = {
{1,0,0,1},
{1,1,0,0},
{0,1,1,0},
{0,0,1,1}
}
step_states8 = {
{1,0,0,0},
{1,1,0,0},
{0,1,0,0},
{0,1,1,0},
{0,0,1,0},
{0,0,1,1},
{0,0,0,1},
{1,0,0,1},
}
step_states = step_states8 -- choose stepping mode
step_numstates = 8 -- change to match number of rows in step_states
step_delay = 20 -- choose speed
step_state = 0 -- updated by step_take-function
step_direction = 1 -- choose step direction -1, 1
step_stepsleft = 0 -- number of steps to move, will de decremented
step_timerid = 4 -- which timer to use for the steps
-- setup pins
for i = 1, 4, 1 do
gpio.mode(stepper_pins[i],gpio.OUTPUT)
end
-- turn off all pins to let motor rest
function step_stopstate()
for i = 1, 4, 1 do
gpio.write(stepper_pins[i], 0)
end
end
-- make stepper take one step
function step_take()
-- jump to the next state in the direction, wrap
step_state = step_state + step_direction
if step_state > step_numstates then
step_state = 1;
elseif step_state < 1 then
step_state = step_numstates
end
--print("step " .. step_state)
-- write the current state to the pins
for i = 1, 4, 1 do
gpio.write(stepper_pins[i], step_states[step_state][i])
end
-- might take another step after step_delay
step_stepsleft = step_stepsleft-1
if step_stepsleft > 0 then
tmr.alarm(step_timerid, step_delay, 0, step_take )
else
step_stopstate()
end
end
-- public method to start moving number of 'int steps' in 'int direction'
function step_move(steps, direction, delay)
tmr.stop(step_timerid)
step_stepsleft = steps
step_direction = direction
step_delay = delay
step_take()
end
-- public method to cancel moving
function step_stop()
tmr.stop(step_timerid)
step_stepsleft = 0
step_stopstate()
end
--step_move(8,(1),20)transfer the file as stepper.lua and run it with
Code: Select all
dofile("stepper.lua")
step_move(8,(1),20)
step_move(8,(-1),20)
-- steps, direction, delay
