kiln_controller/kiln/Adafruit_LEDBackpack.py

94 wiersze
2.6 KiB
Python

#!/usr/bin/python
import time
from copy import copy
from Adafruit_I2C import Adafruit_I2C
# ============================================================================
# LEDBackpack Class
# ============================================================================
class LEDBackpack:
i2c = None
# Registers
__HT16K33_REGISTER_DISPLAY_SETUP = 0x80
__HT16K33_REGISTER_SYSTEM_SETUP = 0x20
__HT16K33_REGISTER_DIMMING = 0xE0
# Blink rate
__HT16K33_BLINKRATE_OFF = 0x00
__HT16K33_BLINKRATE_2HZ = 0x01
__HT16K33_BLINKRATE_1HZ = 0x02
__HT16K33_BLINKRATE_HALFHZ = 0x03
# Display buffer (8x16-bits)
__buffer = [0x0000, 0x0000, 0x0000, 0x0000, \
0x0000, 0x0000, 0x0000, 0x0000 ]
# Constructor
def __init__(self, address=0x70, debug=False):
self.i2c = Adafruit_I2C(address)
self.address = address
self.debug = debug
# Turn the oscillator on
self.i2c.write8(self.__HT16K33_REGISTER_SYSTEM_SETUP | 0x01, 0x00)
# Turn blink off
self.setBlinkRate(self.__HT16K33_BLINKRATE_OFF)
# Set maximum brightness
self.setBrightness(15)
# Clear the screen
self.clear()
def setBrightness(self, brightness):
"Sets the brightness level from 0..15"
if (brightness > 15):
brightness = 15
self.i2c.write8(self.__HT16K33_REGISTER_DIMMING | brightness, 0x00)
def setBlinkRate(self, blinkRate):
"Sets the blink rate"
if (blinkRate > self.__HT16K33_BLINKRATE_HALFHZ):
blinkRate = self.__HT16K33_BLINKRATE_OFF
self.i2c.write8(self.__HT16K33_REGISTER_DISPLAY_SETUP | 0x01 | (blinkRate << 1), 0x00)
def setBufferRow(self, row, value, update=True):
"Updates a single 16-bit entry in the 8*16-bit buffer"
if (row > 7):
return # Prevent buffer overflow
self.__buffer[row] = value # value # & 0xFFFF
if (update):
self.writeDisplay() # Update the display
def getBufferRow(self, row):
"Returns a single 16-bit entry in the 8*16-bit buffer"
if (row > 7):
return
return self.__buffer[row]
def getBuffer(self):
"Returns a copy of the raw buffer contents"
bufferCopy = copy(self.__buffer)
return bufferCopy
def writeDisplay(self):
"Updates the display memory"
bytes = []
for item in self.__buffer:
bytes.append(item & 0xFF)
bytes.append((item >> 8) & 0xFF)
self.i2c.writeList(0x00, bytes)
def clear(self, update=True):
"Clears the display memory"
self.__buffer = [ 0, 0, 0, 0, 0, 0, 0, 0 ]
if (update):
self.writeDisplay()
led = LEDBackpack(0x70)