gfxlcd/gfxlcd/driver/xpt2046/xpt2046.py
2017-07-09 14:32:53 +02:00

68 lines
2.5 KiB
Python

"""XPT2046 touch pabel driver"""
import RPi.GPIO # pylint: disable=I0011,F0401
from gfxlcd.abstract.touch import Touch
class XPT2046(Touch):
"""XPT2046 class"""
def __init__(self, width, height, int_pin=None, callback=None, cs_pin=None, spi=0, speed=1000000):
super().__init__(width, height, int_pin, callback, cs_pin, spi, speed)
self.correction = {
'x': 540,
'y': 50,
'ratio_x': 0.94,
'ratio_y': 1.26,
}
def _get_xy(self, offset_x, offset_y):
"""correct x and y"""
if self.rotate == 0:
return int((offset_x - self.correction['x']) / self.correction['ratio_x']), \
self.height - int((offset_y - self.correction['y']) / self.correction['ratio_y'])
if self.rotate == 90:
return int((offset_y - self.correction['y']) / self.correction['ratio_y']), \
int((offset_x - self.correction['x']) / self.correction['ratio_x']),
if self.rotate == 180:
return self.width - int((offset_x - self.correction['x']) / self.correction['ratio_x']), \
int((offset_y - self.correction['y']) / self.correction['ratio_y'])
if self.rotate == 270:
return self.height - int((offset_y - self.correction['y']) / self.correction['ratio_y']), \
self.width - int((offset_x - self.correction['x']) / self.correction['ratio_x'])
def get_position(self):
"""get touch coords"""
buffer = []
fuse = 40
while len(buffer) < 20 and fuse > 0:
if self.cs_pin:
RPi.GPIO.output(self.cs_pin, 0)
self.spi.xfer2([0x80 | 0x08 | 0x30])
recv = self.spi.readbytes(1)
tc_rz = recv[0] & 0x7f
self.spi.xfer2([0x80 | 0x08 | 0x40])
recv = self.spi.readbytes(1)
tc_rz += (255-recv[0] & 0x7f)
self.spi.xfer2([0x80 | 0x10])
recv = self.spi.readbytes(2)
tc_rx = 1023-((recv[0] << 2)|(recv[1] >> 6))
self.spi.xfer2([0x80 | 0x50])
recv = self.spi.readbytes(2)
tc_ry = ((recv[0] << 2)|(recv[1] >> 6))
if self.cs_pin:
RPi.GPIO.output(self.cs_pin, 1)
if tc_rz > 10:
pos_x, pos_y = self._get_xy(tc_rx, tc_ry)
if self._in_bounds(pos_x, pos_y):
buffer.append((pos_x, pos_y))
fuse -= 1
return self._calculate_avr(buffer)