- Sun Jul 26, 2015 5:19 am
#24287
Thank you for your help! I a new user of the ESP8266.
The code i use was from Abel on an previous post:
Code: Select all-- PCF8574
-- P7 P6 P5 P4 P3 P2 P1 P0
-- D7 D6 D5 D4 (BL) EN RW RS
-- HD44780
id = 0
sda = 4 -- GPIO2
scl = 5 -- GPIO14
dev = 0x27 -- PCF8574
reg = 0x4e -- write
i2c.setup(id, sda, scl, i2c.SLOW)
function send(data)
local bl = 0x00 -- 0x08 = back light on
local value = {}
for i = 1, #data do
table.insert(value, data[i] + bl + 0x04 + rs)
table.insert(value, data[i] + bl + rs) -- fall edge to write
end
i2c.start(id)
i2c.address(id, dev ,i2c.TRANSMITTER)
i2c.write(id, reg, value)
i2c.stop(id)
end
-- init
rs = 0
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
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
}
rs = 1
str = "Hello World!"
for i = 1, #str do
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
The strange why is blinking the "cursor" in the end of the text and do not appear the text.
Thank you in advance.
Last edited by John A on Mon Jul 27, 2015 4:13 pm, edited 1 time in total.
