import smbus
import time
from threading import Thread
import atexit
from colorsys import hsv_to_rgb
try:
import queue
except ImportError:
import Queue as queue
ADDR = 0x3f
__version__ = '0.0.2'
_bus = None
LED_DATA = 7
LED_CLOCK = 6
REG_INPUT = 0x00
REG_OUTPUT = 0x01
REG_POLARITY = 0x02
REG_CONFIG = 0x03
NUM_BUTTONS = 5
BUTTON_A = 0
"""Button A"""
BUTTON_B = 1
"""Button B"""
BUTTON_C = 2
"""Button C"""
BUTTON_D = 3
"""Button D"""
BUTTON_E = 4
"""Button E"""
NAMES = ['A', 'B', 'C', 'D', 'E']
"""Sometimes you want to print the plain text name of the button that's triggered.
You can use::
buttonshim.NAMES[button_index]
To accomplish this.
"""
ERROR_LIMIT = 10
FPS = 60
LED_GAMMA = [
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2,
2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5,
6, 6, 6, 7, 7, 7, 8, 8, 8, 9, 9, 9, 10, 10, 11, 11,
11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 16, 16, 17, 17, 18, 18,
19, 19, 20, 21, 21, 22, 22, 23, 23, 24, 25, 25, 26, 27, 27, 28,
29, 29, 30, 31, 31, 32, 33, 34, 34, 35, 36, 37, 37, 38, 39, 40,
40, 41, 42, 43, 44, 45, 46, 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, 76, 77, 78, 79, 80, 81, 83, 84, 85, 86, 88, 89,
90, 91, 93, 94, 95, 96, 98, 99, 100, 102, 103, 104, 106, 107, 109, 110,
111, 113, 114, 116, 117, 119, 120, 121, 123, 124, 126, 128, 129, 131, 132, 134,
135, 137, 138, 140, 142, 143, 145, 146, 148, 150, 151, 153, 155, 157, 158, 160,
162, 163, 165, 167, 169, 170, 172, 174, 176, 178, 179, 181, 183, 185, 187, 189,
191, 193, 194, 196, 198, 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, 220,
222, 224, 227, 229, 231, 233, 235, 237, 239, 241, 244, 246, 248, 250, 252, 255]
# The LED is an APA102 driven via the i2c IO expander.
# We must set and clear the Clock and Data pins
# Each byte in _reg_queue represents a snapshot of the pin state
_reg_queue = []
_update_queue = []
_brightness = 0.5
_led_queue = queue.Queue()
_t_poll = None
_running = False
_states = 0b00011111
class Handler():
def __init__(self):
self.press = None
self.release = None
self.hold = None
self.hold_time = 0
self.repeat = False
self.repeat_time = 0
self.t_pressed = 0
self.t_repeat = 0
self.hold_fired = False
_handlers = [Handler() for x in range(NUM_BUTTONS)]
def _run():
global _running, _states
_running = True
_last_states = 0b00011111
_errors = 0
while _running:
led_data = None
try:
led_data = _led_queue.get(False)
_led_queue.task_done()
except queue.Empty:
pass
try:
if led_data:
for chunk in _chunk(led_data, 32):
_bus.write_i2c_block_data(ADDR, REG_OUTPUT, chunk)
_states = _bus.read_byte_data(ADDR, REG_INPUT)
except IOError as e:
_errors += 1
if _errors > ERROR_LIMIT:
_running = False
raise IOError("More than {} IO errors have occurred!".format(ERROR_LIMIT))
for x in range(NUM_BUTTONS):
last = (_last_states >> x) & 1
curr = (_states >> x) & 1
handler = _handlers[x]
# If last > curr then it's a transition from 1 to 0
# since the buttons are active low, that's a press event
if last > curr:
handler.t_pressed = time.time()
handler.hold_fired = False
if callable(handler.press):
handler.t_repeat = time.time()
Thread(target=handler.press, args=(x, True)).start()
continue
if last < curr and callable(handler.release):
Thread(target=handler.release, args=(x, False)).start()
continue
if curr == 0:
if callable(handler.hold) and handler.hold_fired == False and (time.time() - handler.t_pressed) > handler.hold_time:
Thread(target=handler.hold, args=(x,)).start()
handler.hold_fired = True
if handler.repeat and callable(handler.press) and (time.time() - handler.t_repeat) > handler.repeat_time:
_handlers[x].t_repeat = time.time()
Thread(target=_handlers[x].press, args=(x, True)).start()
_last_states = _states
time.sleep(1.0 / FPS)
def _quit():
global _running
if _running:
_led_queue.join()
set_pixel(0, 0, 0)
_led_queue.join()
_running = False
_t_poll.join()
def setup():
global _t_poll, _bus
if _bus is not None:
return
_bus = smbus.SMBus(1)
_bus.write_byte_data(ADDR, REG_CONFIG, 0b00011111)
_bus.write_byte_data(ADDR, REG_POLARITY, 0b00000000)
_bus.write_byte_data(ADDR, REG_OUTPUT, 0b00000000)
_t_poll = Thread(target=_run)
_t_poll.daemon = True
_t_poll.start()
set_pixel(0, 0, 0)
atexit.register(_quit)
def _set_bit(pin, value):
global _reg_queue
if value:
_reg_queue[-1] |= (1 << pin)
else:
_reg_queue[-1] &= ~(1 << pin)
def _next():
global _reg_queue
if len(_reg_queue) == 0:
_reg_queue = [0b00000000]
else:
_reg_queue.append(_reg_queue[-1])
def _enqueue():
global _reg_queue
_led_queue.put(_reg_queue)
_reg_queue = []
def _chunk(l, n):
for i in range(0, len(l)+1, n):
yield l[i:i + n]
def _write_byte(byte):
for x in range(8):
_next()
_set_bit(LED_CLOCK, 0)
_set_bit(LED_DATA, byte & 0b10000000)
_next()
_set_bit(LED_CLOCK, 1)
byte <<= 1
[docs]def on_hold(buttons, handler=None, hold_time=2):
"""Attach a hold handler to one or more buttons.
This handler is fired when you hold a button for hold_time seconds.
When fired it will run in its own Thread.
It will be passed one argument, the button index::
@buttonshim.on_press(buttonshim.BUTTON_A)
def handler(button):
# Your code here
:param buttons: A single button, or a list of buttons
:param handler: Optional: a function to bind as the handler
:param hold_time: Optional: the hold time in seconds (default 2)
"""
setup()
if buttons is None:
buttons = [BUTTON_A, BUTTON_B, BUTTON_C, BUTTON_D, BUTTON_E]
if isinstance(buttons, int):
buttons = [buttons]
def attach_handler(handler):
for button in buttons:
_handlers[button].hold = handler
_handlers[button].hold_time = hold_time
if handler is not None:
attach_handler(handler)
else:
return attach_handler
[docs]def on_press(buttons, handler=None, repeat=False, repeat_time=0.5):
"""Attach a press handler to one or more buttons.
This handler is fired when you press a button.
When fired it will be run in its own Thread.
It will be passed two arguments, the button index and a
boolean indicating whether the button has been pressed/released::
@buttonshim.on_press(buttonshim.BUTTON_A)
def handler(button, pressed):
# Your code here
:param buttons: A single button, or a list of buttons
:param handler: Optional: a function to bind as the handler
:param repeat: Optional: Repeat the handler if the button is held
:param repeat_time: Optional: Time, in seconds, after which to repeat
"""
setup()
if buttons is None:
buttons = [BUTTON_A, BUTTON_B, BUTTON_C, BUTTON_D, BUTTON_E]
if isinstance(buttons, int):
buttons = [buttons]
def attach_handler(handler):
for button in buttons:
_handlers[button].press = handler
_handlers[button].repeat = repeat
_handlers[button].repeat_time = repeat_time
if handler is not None:
attach_handler(handler)
else:
return attach_handler
[docs]def on_release(buttons=None, handler=None):
"""Attach a release handler to one or more buttons.
This handler is fired when you let go of a button.
When fired it will be run in its own Thread.
It will be passed two arguments, the button index and a
boolean indicating whether the button has been pressed/released::
@buttonshim.on_release(buttonshim.BUTTON_A)
def handler(button, pressed):
# Your code here
:param buttons: A single button, or a list of buttons
:param handler: Optional: a function to bind as the handler
"""
setup()
if buttons is None:
buttons = [BUTTON_A, BUTTON_B, BUTTON_C, BUTTON_D, BUTTON_E]
if isinstance(buttons, int):
buttons = [buttons]
def attach_handler(handler):
for button in buttons:
_handlers[button].release = handler
if handler is not None:
attach_handler(handler)
else:
return attach_handler
def set_brightness(brightness):
global _brightness
setup()
if not isinstance(brightness, int) and not isinstance(brightness, float):
raise ValueError("Brightness should be an int or float")
if brightness < 0.0 or brightness > 1.0:
raise ValueError("Brightness should be between 0.0 and 1.0")
_brightness = brightness
[docs]def set_pixel(r, g, b):
"""Set the Button SHIM RGB pixel
Display an RGB colour on the Button SHIM pixel.
:param r: Amount of red, from 0 to 255
:param g: Amount of green, from 0 to 255
:param b: Amount of blue, from 0 to 255
You can use HTML colours directly with hexadecimal notation in Python. EG::
buttonshim.set_pixel(0xFF, 0x00, 0xFF)
"""
setup()
if not isinstance(r, int) or r < 0 or r > 255:
raise ValueError("Argument r should be an int from 0 to 255")
if not isinstance(g, int) or g < 0 or g > 255:
raise ValueError("Argument g should be an int from 0 to 255")
if not isinstance(b, int) or b < 0 or b > 255:
raise ValueError("Argument b should be an int from 0 to 255")
r, g, b = [int(x * _brightness) for x in (r, g, b)]
_write_byte(0)
_write_byte(0)
_write_byte(0b11101111)
_write_byte(LED_GAMMA[b & 0xff])
_write_byte(LED_GAMMA[g & 0xff])
_write_byte(LED_GAMMA[r & 0xff])
_write_byte(0)
_write_byte(0)
_enqueue()
if __name__ == "__main__":
@on_press([BUTTON_A, BUTTON_B, BUTTON_C, BUTTON_D, BUTTON_E])
def handle_press(button, state):
print("PRESS: Button {} ({}) is {}".format(button, NAMES[button], state))
@on_release([BUTTON_A, BUTTON_B, BUTTON_C, BUTTON_D, BUTTON_E])
def handle_release(button, state):
print("RELEASE: Button {} ({}) is {}".format(button, NAMES[button], state))
while True:
hue = (time.time() * 100 % 360) / 360.0
r, g, b = [int(c * 255) for c in hsv_to_rgb(hue, 1.0, 1.0)]
set_pixel(r, g, b)
time.sleep(0.1)