forked from adafruit/Adafruit_CircuitPython_FocalTouch
-
Notifications
You must be signed in to change notification settings - Fork 0
/
adafruit_focaltouch.py
154 lines (125 loc) · 5.14 KB
/
adafruit_focaltouch.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
# The MIT License (MIT)
#
# Copyright (c) 2017 ladyada for adafruit industries
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
"""
`adafruit_focaltouch`
====================================================
CircuitPython driver for common low-cost FocalTech capacitive touch chips.
Currently supports FT6206 & FT6236.
* Author(s): ladyada
Implementation Notes
--------------------
**Hardware:**
* Adafruit `2.8" TFT LCD with Cap Touch Breakout Board w/MicroSD Socket
<http://www.adafruit.com/product/2090>`_ (Product ID: 2090)
* Adafruit `2.8" TFT Touch Shield for Arduino w/Capacitive Touch
<http://www.adafruit.com/product/1947>`_ (Product ID: 1947)
**Software and Dependencies:**
* Adafruit CircuitPython firmware for the ESP8622 and M0-based boards:
https://github.com/adafruit/circuitpython/releases
* Adafruit's Bus Device library (when using I2C/SPI):
https://github.com/adafruit/Adafruit_CircuitPython_BusDevice
"""
# imports
__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_FocalTouch.git"
try:
import struct
except ImportError:
import ustruct as struct
from adafruit_bus_device.i2c_device import I2CDevice
from micropython import const
_FT6206_DEFAULT_I2C_ADDR = 0x38
_FT6XXX_REG_DATA = const(0x00)
_FT6XXX_REG_NUMTOUCHES = const(0x02)
_FT6XXX_REG_THRESHHOLD = const(0x80)
_FT6XXX_REG_POINTRATE = const(0x88)
_FT6XXX_REG_LIBH = const(0xA1)
_FT6XXX_REG_LIBL = const(0xA2)
_FT6XXX_REG_CHIPID = const(0xA3)
_FT6XXX_REG_FIRMVERS = const(0xA6)
_FT6XXX_REG_VENDID = const(0xA8)
_FT6XXX_REG_RELEASE = const(0xAF)
class Adafruit_FocalTouch:
"""
A driver for the FocalTech capacitive touch sensor.
"""
_debug = False
chip = None
def __init__(self, i2c, address=_FT6206_DEFAULT_I2C_ADDR, debug=False):
self._i2c = I2CDevice(i2c, address)
self._debug = debug
chip_data = self._read(_FT6XXX_REG_LIBH, 8)
lib_ver, chip_id, _, _, firm_id, _, vend_id = struct.unpack('>HBBBBBB', chip_data)
if vend_id != 0x11:
raise RuntimeError("Did not find FT chip")
if chip_id == 0x06:
self.chip = "FT6206"
elif chip_id == 0x64:
self.chip = "FT6236"
if debug:
print("Library vers %04X" % lib_ver)
print("Firmware ID %02X" % firm_id)
print("Point rate %d Hz" % self._read(_FT6XXX_REG_POINTRATE, 1)[0])
print("Thresh %d" % self._read(_FT6XXX_REG_THRESHHOLD, 1)[0])
@property
def touched(self):
""" Returns the number of touches currently detected """
return self._read(_FT6XXX_REG_NUMTOUCHES, 1)[0]
# pylint: disable=unused-variable
@property
def touches(self):
"""
Returns a list of touchpoint dicts, with 'x' and 'y' containing the
touch coordinates, and 'id' as the touch # for multitouch tracking
"""
touchpoints = []
data = self._read(_FT6XXX_REG_DATA, 32)
for i in range(2):
point_data = data[i*6+3 : i*6+9]
if all([i == 0xFF for i in point_data]):
continue
#print([hex(i) for i in point_data])
x, y, weight, misc = struct.unpack('>HHBB', point_data)
#print(x, y, weight, misc)
touch_id = y >> 12
x &= 0xFFF
y &= 0xFFF
point = {'x':x, 'y':y, 'id':touch_id}
touchpoints.append(point)
return touchpoints
# pylint: enable=unused-variable
def _read(self, register, length):
"""Returns an array of 'length' bytes from the 'register'"""
with self._i2c as i2c:
i2c.write(bytes([register & 0xFF]))
result = bytearray(length)
i2c.readinto(result)
if self._debug:
print("\t$%02X => %s" % (register, [hex(i) for i in result]))
return result
def _write(self, register, values):
"""Writes an array of 'length' bytes to the 'register'"""
with self._i2c as i2c:
values = [(v & 0xFF) for v in [register]+values]
i2c.write(bytes(values))
if self._debug:
print("\t$%02X <= %s" % (values[0], [hex(i) for i in values[1:]]))