fix wrong path
This commit is contained in:
@@ -0,0 +1,202 @@
|
||||
Metadata-Version: 1.1
|
||||
Name: smbus2
|
||||
Version: 0.2.0
|
||||
Summary: smbus2 is a drop-in replacement for smbus-cffi/smbus-python in pure Python
|
||||
Home-page: https://github.com/kplindegaard/smbus2
|
||||
Author: Karl-Petter Lindegaard
|
||||
Author-email: kp.lindegaard@gmail.com
|
||||
License: MIT
|
||||
Description: smbus2
|
||||
======
|
||||
A drop-in replacement for smbus-cffi/smbus-python in pure Python
|
||||
|
||||
|travis|
|
||||
|
||||
.. |travis| image:: https://travis-ci.org/kplindegaard/smbus2.svg?branch=master
|
||||
:target: https://travis-ci.org/kplindegaard/smbus2
|
||||
|
||||
Introduction
|
||||
============
|
||||
|
||||
smbus2 is (yet another) pure Python implementation of the `python-smbus <http://www.lm-sensors.org/browser/i2c-tools/trunk/py-smbus/>`_ package.
|
||||
|
||||
It was designed from the ground up with two goals in mind:
|
||||
|
||||
1. It should be a drop-in replacement of smbus. The syntax shall be the same.
|
||||
2. Use the inherent i2c structs and unions to a greater extent than other pure Python implementations like `pysmbus <https://github.com/bjornt/pysmbus>`_ does. By doing so, it will be more feature complete and easier to extend.
|
||||
|
||||
Currently supported features are:
|
||||
|
||||
* Get i2c capabilities (I2C_FUNCS)
|
||||
* read_byte
|
||||
* write_byte
|
||||
* read_byte_data
|
||||
* write_byte_data
|
||||
* read_word_data
|
||||
* write_word_data
|
||||
* read_i2c_block_data
|
||||
* write_i2c_block_data
|
||||
* i2c_rdwr - *combined write/read transactions with repeated start*
|
||||
|
||||
It is developed on Python 2.7 but works without any modifications in Python 3.X too.
|
||||
|
||||
SMBus code examples
|
||||
===================
|
||||
|
||||
smbus2 installs next to smbus as the package, so it's not really a 100% replacement. You must change the module name.
|
||||
|
||||
Example 1a: Read a byte
|
||||
-----------------------
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBus
|
||||
|
||||
# Open i2c bus 1 and read one byte from address 80, offset 0
|
||||
bus = SMBus(1)
|
||||
b = bus.read_byte_data(80, 0)
|
||||
print(b)
|
||||
bus.close()
|
||||
|
||||
Example 1b: Read a byte using 'with'
|
||||
------------------------------------
|
||||
|
||||
This is the very same example but safer to use since the smbus will be closed automatically when exiting the with block.
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBusWrapper
|
||||
|
||||
with SMBusWrapper(1) as bus:
|
||||
b = bus.read_byte_data(80, 0)
|
||||
print(b)
|
||||
|
||||
Example 2: Read a block of data
|
||||
-------------------------------
|
||||
|
||||
You can read up to 32 bytes at once.
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBusWrapper
|
||||
|
||||
with SMBusWrapper(1) as bus:
|
||||
# Read a block of 16 bytes from address 80, offset 0
|
||||
block = bus.read_i2c_block_data(80, 0, 16)
|
||||
# Returned value is a list of 16 bytes
|
||||
print(block)
|
||||
|
||||
Example 3: Write a byte
|
||||
-----------------------
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBusWrapper
|
||||
|
||||
with SMBusWrapper(1) as bus:
|
||||
# Write a byte to address 80, offset 0
|
||||
data = 45
|
||||
bus.write_byte_data(80, 0, data)
|
||||
|
||||
Example 4: Write a block of data
|
||||
--------------------------------
|
||||
|
||||
It is possible to write 32 bytes at the time, but I have found that error-prone. Write less and add a delay in between if you run into trouble.
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBusWrapper
|
||||
|
||||
with SMBusWrapper(1) as bus:
|
||||
# Write a block of 8 bytes to address 80 from offset 0
|
||||
data = [1, 2, 3, 4, 5, 6, 7, 8]
|
||||
bus.write_i2c_block_data(80, 0, data)
|
||||
|
||||
|
||||
I2C
|
||||
===
|
||||
|
||||
Starting with v0.2, the smbus2 library also has support for combined read and write transactions. *i2c_rdwr* is not really a SMBus feature but comes in handy when the master needs to:
|
||||
|
||||
1. read or write bulks of data larger than SMBus' 32 bytes limit.
|
||||
1. write some data and then read from the slave with a repeated start and no stop bit between.
|
||||
|
||||
Each operation is represented by a *i2c_msg* message object.
|
||||
|
||||
|
||||
Example 5: Single i2c_rdwr
|
||||
--------------------------
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBus, ic_msg
|
||||
|
||||
with SMBusWrapper(1) as bus:
|
||||
# Read 64 bytes from address 80
|
||||
msg = i2c_msg.read(80, 64)
|
||||
bus.i2c_rdwr(msg)
|
||||
|
||||
# Write some bytes to address 80
|
||||
msg = i2c_msg.write(80, [65, 66, 67, 68])
|
||||
bus.i2c_rdwr(msg)
|
||||
|
||||
|
||||
Example 6: Dual i2c_rdwr
|
||||
------------------------
|
||||
|
||||
To perform dual operations just add more i2c_msg instances to the bus call:
|
||||
|
||||
.. code:: python
|
||||
|
||||
from smbus2 import SMBus, ic_msg
|
||||
|
||||
# Single transaction writing two bytes then read two at address 80
|
||||
write = i2c_msg.write(80, [40, 50])
|
||||
read = i2c_msg.read(80, 2)
|
||||
with SMBusWrapper(1) as bus:
|
||||
bus.i2c_rdwr(write, read)
|
||||
|
||||
|
||||
Example 7: Access i2c_msg data
|
||||
------------------------------
|
||||
|
||||
All data is contained in the i2c_msg instances. Here are some data access alternatives.
|
||||
|
||||
.. code:: python
|
||||
|
||||
# 1: Convert message content to list
|
||||
msg = i2c.write(60, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
|
||||
data = list(msg) # data = [1, 2, 3, ...]
|
||||
print(len(data)) # => 10
|
||||
|
||||
# 2: i2c_msg is iterable
|
||||
for value in msg:
|
||||
print(value)
|
||||
|
||||
# 3: Through i2c_msg properties
|
||||
for k in range(msg.len):
|
||||
print(msg.buf[k])
|
||||
|
||||
|
||||
Installation instructions
|
||||
=========================
|
||||
|
||||
smbus2 is pure Python code and requires no compilation. Installation is easy:
|
||||
|
||||
.. code:: bash
|
||||
|
||||
python setup.py install
|
||||
|
||||
Or just use pip
|
||||
|
||||
.. code:: bash
|
||||
|
||||
pip install smbus2
|
||||
|
||||
Keywords: smbus,smbus2,python,i2c,raspberrypi,linux
|
||||
Platform: UNKNOWN
|
||||
Classifier: Development Status :: 4 - Beta
|
||||
Classifier: Topic :: Utilities
|
||||
Classifier: License :: OSI Approved :: MIT License
|
||||
Classifier: Programming Language :: Python :: 2.7
|
||||
Classifier: Programming Language :: Python :: 3
|
||||
Reference in New Issue
Block a user