Embedded Systems LM5p-GSM, Руководство по эксплуатации продукта

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16. DMX interconnection with LM
DMX protocol support is realized upon RS485 serial port.
DMX function
Add the following user library in
Scripting

User libraries .
local luadmx =
require ( 'luadmx' )
module ( 'DMX' , package. seeall )
local DMX = {}
-- default params
local defaults = {
-- storage key
skey = 'dmx_line_1' ,
-- RS-485 port
port = '/dev/RS485' ,
-- number of calls per second
resolution = 20 ,
-- total number of channels to use
channels = 3 ,
-- transition time in seconds, does not include DMX transfer time
transition = 2 ,
}
-- value setter
function set ( chan, val, key )
key = key or defaults. skey
chan = tonumber (chan) or 0
val = tonumber (val) or - 1
-- validate channel number and value
if chan >= 1 and chan <= 512 and val >= 0 and val <= 255 then
storage. exec ( 'lset' , key, chan - 1 , val)
end
end
-- value getter
function get ( chan, key )
local res, val
key = key or defaults. skey
chan = tonumber (chan) or 0
-- validate channel number and value
if chan >= 1 and chan <= 512 then
res = storage. exec ( 'lrange' , key, chan - 1 , chan - 1 )
if type (res) == 'table' then
val = tonumber (res[ 1 ])
end
end