- Mon Jul 27, 2015 4:12 pm
#24413
I just solve a few problems and now is even working with two lines!
Code: Select all
-- PCF8574
-- P7 P6 P5 P4 P3 P2 P1 P0
-- D7 D6 D5 D4 (BL) EN RW RS
-- HD44780
id = 0x00
sda = 3 -- GPIO2
scl = 4 -- GPIO14
dev = 0x23 -- PCF8574
reg = 0x4e -- write
var1 = 0x04
i2c.setup(id, sda, scl, i2c.SLOW)
function send(data)
local bl = 0x08 -- 0x08 = back light on
local ls = 0x01
local value = {}
-- print (#data)
for i = 1, #data do
table.insert(value , data[i] + bl + var1 + rs)
-- print (value , data[i], rs)
table.insert(value , data[i] + bl + rs) -- fall edge to write
-- print (value , data[i] , rs)
end
i2c.start(id)
i2c.address(id, dev ,i2c.TRANSMITTER)
i2c.write(id,value)
-- print (value)
i2c.stop(id)
end
-- init
rs = 0x00
send({0x30})
tmr.delay(4100)
send({0x30})
tmr.delay(100)
send({0x30})
send({0x20, 0x20, 0x80}) -- 4 bit, 2 line
send({0x00, 0x10}) -- display clear
send({0x00, 0xf0}) -- display on
print ( " Finish the setup")
nibble = {
["0"] = 0x00,
["1"] = 0x10,
["2"] = 0x20,
["3"] = 0x30,
["4"] = 0x40,
["5"] = 0x50,
["6"] = 0x60,
["7"] = 0x70,
["8"] = 0x80,
["9"] = 0x90,
["a"] = 0xa0,
["b"] = 0xb0,
["c"] = 0xc0,
["d"] = 0xd0,
["e"] = 0xe0,
["f"] = 0xf0
}
str = "Hello world!!!! Hello world!!!!"
for i = 1, #str do
if i~=17 then
rs = 0x01
local char = string.byte(string.sub(str, i, i))
send({
nibble[string.sub(string.format("%x", char), 1, -2)],
nibble[string.sub(string.format("%x", char), 2)]})
else
rs = 0x00
send({0xC0,0x00}) -- new line
rs = 0x01
local char = string.byte(string.sub(str, i, i))
send({
nibble[string.sub(string.format("%x", char), 1, -2)],
nibble[string.sub(string.format("%x", char), 2)]})
end
end
