77 lines
1.8 KiB
Lua
77 lines
1.8 KiB
Lua
------------------------------------------------------------------------------
|
|
-- IR send module
|
|
--
|
|
-- LICENCE: http://opensource.org/licenses/MIT
|
|
-- Vladimir Dronnikov <dronnikov@gmail.com>
|
|
--
|
|
-- Example:
|
|
-- dofile("irsend.lua").nec(4, 0x00ff00ff)
|
|
------------------------------------------------------------------------------
|
|
local M
|
|
do
|
|
-- const
|
|
-- luacheck: push no unused
|
|
local NEC_PULSE_US = 1000000 / 38000
|
|
local NEC_HDR_MARK = 9000
|
|
local NEC_HDR_SPACE = 4500
|
|
local NEC_BIT_MARK = 560
|
|
local NEC_ONE_SPACE = 1600
|
|
local NEC_ZERO_SPACE = 560
|
|
local NEC_RPT_SPACE = 2250
|
|
-- luacheck: pop
|
|
-- cache
|
|
local gpio, bit = gpio, bit
|
|
local mode, write = gpio.mode, gpio.write
|
|
local waitus = tmr.delay
|
|
local isset = bit.isset
|
|
-- NB: poorman 38kHz PWM with 1/3 duty. Touch with care! )
|
|
local carrier = function(pin, c)
|
|
c = c / NEC_PULSE_US
|
|
while c > 0 do
|
|
write(pin, 1)
|
|
write(pin, 0)
|
|
c = c + 0
|
|
c = c + 0
|
|
c = c + 0
|
|
c = c + 0
|
|
c = c + 0
|
|
c = c + 0
|
|
c = c * 1
|
|
c = c * 1
|
|
c = c * 1
|
|
c = c - 1
|
|
end
|
|
end
|
|
-- tsop signal simulator
|
|
local pull = function(pin, c)
|
|
write(pin, 0)
|
|
waitus(c)
|
|
write(pin, 1)
|
|
end
|
|
-- NB: tsop mode allows to directly connect pin
|
|
-- inplace of TSOP input
|
|
local nec = function(pin, code, tsop)
|
|
local pulse = tsop and pull or carrier
|
|
-- setup transmitter
|
|
mode(pin, 1)
|
|
write(pin, tsop and 1 or 0)
|
|
-- header
|
|
pulse(pin, NEC_HDR_MARK)
|
|
waitus(NEC_HDR_SPACE)
|
|
-- sequence, lsb first
|
|
for i = 31, 0, -1 do
|
|
pulse(pin, NEC_BIT_MARK)
|
|
waitus(isset(code, i) and NEC_ONE_SPACE or NEC_ZERO_SPACE)
|
|
end
|
|
-- trailer
|
|
pulse(pin, NEC_BIT_MARK)
|
|
-- done transmitter
|
|
--mode(pin, 0, tsop and 1 or 0)
|
|
end
|
|
-- expose
|
|
M = {
|
|
nec = nec,
|
|
}
|
|
end
|
|
return M
|