------------------------------------------------------------------------------ -- IR send module -- -- LICENCE: http://opensource.org/licenses/MIT -- Vladimir Dronnikov -- -- Example: -- dofile("irsend.lua").nec(4, 0x00ff00ff) ------------------------------------------------------------------------------ local M do -- const 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 -- 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