Ich bin nun nach einigem Suchen auf die Code gestoßen, der jedoch nicht für µPython geschrieben ist.
#!/usr/bin/python
# Copyright 2016-2019 Florian Mueller (contact@petrockblock.com)
#
# 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.
import time
import RPi.GPIO as GPIO
import spidev
class MCP23S17(object):
"""This class provides an abstraction of the GPIO expander MCP23S17
for the Raspberry Pi.
It is depndent on the Python packages spidev and RPi.GPIO, which can
be get from https://pypi.python.org/pypi/RPi.GPIO/0.5.11 and
https://pypi.python.org/pypi/spidev.
"""
PULLUP_ENABLED = 0
PULLUP_DISABLED = 1
DIR_INPUT = 0
DIR_OUTPUT = 1
LEVEL_LOW = 0
LEVEL_HIGH = 1
"""Register addresses as documentined in the technical data sheet at
http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
"""
MCP23S17_IODIRA = 0x00
MCP23S17_IODIRB = 0x01
MCP23S17_IPOLA = 0x2
MCP23S17_IPOLB = 0x3
MCP23S17_GPIOA = 0x12
MCP23S17_GPIOB = 0x13
MCP23S17_OLATA = 0x14
MCP23S17_OLATB = 0x15
MCP23S17_IOCON = 0x0A
MCP23S17_GPPUA = 0x0C
MCP23S17_GPPUB = 0x0D
"""Bit field flags as documentined in the technical data sheet at
http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
"""
IOCON_UNUSED = 0x01
IOCON_INTPOL = 0x02
IOCON_ODR = 0x04
IOCON_HAEN = 0x08
IOCON_DISSLW = 0x10
IOCON_SEQOP = 0x20
IOCON_MIRROR = 0x40
IOCON_BANK_MODE = 0x80
IOCON_INIT = 0x28 # IOCON_SEQOP and IOCON_HAEN from above
MCP23S17_CMD_WRITE = 0x40
MCP23S17_CMD_READ = 0x41
def __init__(self, bus=0, pin_cs=0, pin_reset=-1, device_id=0x00):
"""
Constructor
Initializes all attributes with 0.
Keyword arguments:
device_id -- The device ID of the component, i.e., the hardware address (default 0)
pin_cs -- The Chip Select pin of the MCP, default 0
pin_reset -- The Reset pin of the MCP
"""
self.device_id = device_id
self._GPIOA = 0
self._GPIOB = 0
self._IODIRA = 0
self._IODIRB = 0
self._GPPUA = 0
self._GPPUB = 0
self._pin_reset = pin_reset
self._bus = bus
self._pin_cs = pin_cs
self._spimode = 0b00
self._spi = spidev.SpiDev()
self.isInitialized = False
def open(self):
"""Initializes the MCP23S17 with hardware-address access
and sequential operations mode.
"""
self._setupGPIO()
self._spi.open(self._bus, self._pin_cs)
self.isInitialized = True
self._writeRegister(MCP23S17.MCP23S17_IOCON, MCP23S17.IOCON_INIT)
# set defaults
for index in range(0, 15):
self.setDirection(index, MCP23S17.DIR_INPUT)
self.setPullupMode(index, MCP23S17.PULLUP_ENABLED)
def close(self):
"""Closes the SPI connection that the MCP23S17 component is using.
"""
self._spi.close()
self.isInitialized = False
def setPullupMode(self, pin, mode):
"""Enables or disables the pull-up mode for input pins.
Parameters:
pin -- The pin index (0 - 15)
mode -- The pull-up mode (MCP23S17.PULLUP_ENABLED, MCP23S17.PULLUP_DISABLED)
"""
assert pin < 16
assert (mode == MCP23S17.PULLUP_ENABLED) or (mode == MCP23S17.PULLUP_DISABLED)
assert self.isInitialized
if pin < 8:
register = MCP23S17.MCP23S17_GPPUA
data = self._GPPUA
noshifts = pin
else:
register = MCP23S17.MCP23S17_GPPUB
noshifts = pin & 0x07
data = self._GPPUB
if mode == MCP23S17.PULLUP_ENABLED:
data |= (1 << noshifts)
else:
data &= (~(1 << noshifts))
self._writeRegister(register, data)
if pin < 8:
self._GPPUA = data
else:
self._GPPUB = data
def setDirection(self, pin, direction):
"""Sets the direction for a given pin.
Parameters:
pin -- The pin index (0 - 15)
direction -- The direction of the pin (MCP23S17.DIR_INPUT, MCP23S17.DIR_OUTPUT)
"""
assert (pin < 16)
assert ((direction == MCP23S17.DIR_INPUT) or (direction == MCP23S17.DIR_OUTPUT))
assert self.isInitialized
if pin < 8:
register = MCP23S17.MCP23S17_IODIRA
data = self._IODIRA
noshifts = pin
else:
register = MCP23S17.MCP23S17_IODIRB
noshifts = pin & 0x07
data = self._IODIRB
if direction == MCP23S17.DIR_INPUT:
data |= (1 << noshifts)
else:
data &= (~(1 << noshifts))
self._writeRegister(register, data)
if (pin < 8):
self._IODIRA = data
else:
self._IODIRB = data
def digitalRead(self, pin):
"""Reads the logical level of a given pin.
Parameters:
pin -- The pin index (0 - 15)
Returns:
- MCP23S17.LEVEL_LOW, if the logical level of the pin is low,
- MCP23S17.LEVEL_HIGH, otherwise.
"""
assert self.isInitialized
assert (pin < 16)
if pin < 8:
self._GPIOA = self._readRegister(MCP23S17.MCP23S17_GPIOA)
if (self._GPIOA & (1 << pin)) != 0:
return MCP23S17.LEVEL_HIGH
else:
return MCP23S17.LEVEL_LOW
else:
self._GPIOB = self._readRegister(MCP23S17.MCP23S17_GPIOB)
pin &= 0x07
if (self._GPIOB & (1 << pin)) != 0:
return MCP23S17.LEVEL_HIGH
else:
return MCP23S17.LEVEL_LOW
def digitalWrite(self, pin, level):
"""Sets the level of a given pin.
Parameters:
pin -- The pin index (0 - 15)
level -- The logical level to be set (LEVEL_LOW, LEVEL_HIGH)
"""
assert self.isInitialized
assert (pin < 16)
assert (level == MCP23S17.LEVEL_HIGH) or (level == MCP23S17.LEVEL_LOW)
if pin < 8:
register = MCP23S17.MCP23S17_GPIOA
data = self._GPIOA
noshifts = pin
else:
register = MCP23S17.MCP23S17_GPIOB
noshifts = pin & 0x07
data = self._GPIOB
if level == MCP23S17.LEVEL_HIGH:
data |= (1 << noshifts)
else:
data &= (~(1 << noshifts))
self._writeRegister(register, data)
if (pin < 8):
self._GPIOA = data
else:
self._GPIOB = data
def writeGPIO(self, data):
"""Sets the data port value for all pins.
Parameters:
data - The 16-bit value to be set.
"""
assert self.isInitialized
self._GPIOA = (data & 0xFF)
self._GPIOB = (data >> 8)
self._writeRegisterWord(MCP23S17.MCP23S17_GPIOA, data)
def readGPIO(self):
"""Reads the data port value of all pins.
Returns:
- The 16-bit data port value
"""
assert self.isInitialized
data = self._readRegisterWord(MCP23S17.MCP23S17_GPIOA)
self._GPIOA = (data & 0xFF)
self._GPIOB = (data >> 8)
return data
def _writeRegister(self, register, value):
assert self.isInitialized
command = MCP23S17.MCP23S17_CMD_WRITE | (self.device_id << 1)
self._setSpiMode(self._spimode)
self._spi.xfer2([command, register, value])
def _readRegister(self, register):
assert self.isInitialized
command = MCP23S17.MCP23S17_CMD_READ | (self.device_id << 1)
self._setSpiMode(self._spimode)
data = self._spi.xfer2([command, register, 0])
return data[2]
def _readRegisterWord(self, register):
assert self.isInitialized
buffer = [0, 0]
buffer[0] = self._readRegister(register)
buffer[1] = self._readRegister(register + 1)
return (buffer[1] << 8) | buffer[0]
def _writeRegisterWord(self, register, data):
assert self.isInitialized
self._writeRegister(register, data & 0xFF)
self._writeRegister(register + 1, data >> 8)
def _setupGPIO(self):
GPIO.setwarnings(False)
GPIO.setmode(GPIO.BOARD)
if self._pin_reset != -1:
GPIO.setup(self._pin_reset, GPIO.OUT)
GPIO.output(self._pin_reset, True)
def _setSpiMode(self, mode):
if self._spi.mode != mode:
self._spi.mode = mode
self._spi.xfer2([0]) # dummy write, to force CLK to correct level
if __name__ == '__main__':
"""The following demo periodically toggles the level of
all pins of two MCP23S17 conponents.
"""
from RPiMCP23S17 import MCP23S17
import time
# you might also want to use the parameters bus, pin_cs, or pin_reset
# to match your hardware setup
mcp1 = MCP23S17.MCP23S17(device_id=0x00)
mcp2 = MCP23S17.MCP23S17(device_id=0x01)
mcp1.open()
mcp2.open()
for x in range(0, 16):
mcp1.setDirection(x, mcp1.DIR_OUTPUT)
mcp2.setDirection(x, mcp1.DIR_OUTPUT)
print("Starting blinky on all pins (CTRL+C to quit)")
while (True):
for x in range(0, 16):
mcp1.digitalWrite(x, MCP23S17.MCP23S17.LEVEL_HIGH)
mcp2.digitalWrite(x, MCP23S17.MCP23S17.LEVEL_HIGH)
time.sleep(1)
for x in range(0, 16):
mcp1.digitalWrite(x, MCP23S17.MCP23S17.LEVEL_LOW)
mcp2.digitalWrite(x, MCP23S17.MCP23S17.LEVEL_LOW)
time.sleep(1)
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Dieser kann, das habe ich nun auch an einem 3b+ getestet mit den benötigten 4x MCP23S17 an einem BUS, mit einer CS Leitung umgehen.
