Adafruit_CircuitPython_DS3502/adafruit_ds3502.py

103 lines
3.5 KiB
Python

# The MIT License (MIT)
#
# Copyright (c) 2019 Bryan Siepert 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
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
"""
`adafruit_ds3502`
================================================================================
CircuitPython library for the Maxim DS3502 I2C Digital Potentionmeter
* Author(s): Bryan Siepert
Implementation Notes
--------------------
**Hardware:**
* `Adafruit DS3502 <https://www.adafruit.com/product/4286>`_
**Software and Dependencies:**
* Adafruit CircuitPython firmware for the supported boards:
https://github.com/adafruit/circuitpython/releases
* Adafruit's Bus Device library: https://github.com/adafruit/Adafruit_CircuitPython_BusDevice
* Adafruit's Register library: https://github.com/adafruit/Adafruit_CircuitPython_Register
"""
# imports
__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_DS3502.git"
from time import sleep
from micropython import const
from adafruit_register.i2c_struct import UnaryStruct
from adafruit_register.i2c_bit import RWBit
import adafruit_bus_device.i2c_device as i2cdevice
_REG_WIPER = const(0x00) # Wiper value register (R/W)
_REG_CONTROL = const(0x02) # Configuration Register (R/W)
class DS3502:
"""Driver for the DS3502 I2C Digital Potentiometer.
:param ~busio.I2C i2c_bus: The I2C bus the DS3502 is connected to.
:param address: The I2C device address for the sensor. Default is ``0x40``.
"""
def __init__(self, i2c_bus, address=0x28):
self.i2c_device = i2cdevice.I2CDevice(i2c_bus, address)
# set to mode 1 on init to not write to the IVR every time you set
self._write_only_to_wiper = True
_wiper = UnaryStruct(_REG_WIPER, ">B")
_write_only_to_wiper = RWBit(_REG_CONTROL, 7)
@property
def wiper(self):
"""The value of the potentionmeter's wiper.
:param wiper_value: The value from 0-127 to set the wiper to.
"""
return self._wiper
@wiper.setter
def wiper(self, value):
if value < 0 or value > 127:
raise ValueError("wiper must be from 0-127")
self._wiper = value
def set_default(self, default):
"""Sets the wiper's default value and current value to the given value
:param new_default: The value from 0-127 to set as the wiper's default.
"""
self._write_only_to_wiper = False
self.wiper = default
sleep(0.1) # wait for write to eeprom to finish
self._write_only_to_wiper = True