Python example code for using i2c

Duo
1

Has anyone used Python (probably with smbus) to access I2C on the Duo boards?
If so, do you have any example code you can share?
I’ve seen the C code using /dev/i2cdev-x and ioctl, but I would rather use a cleaner interface, such as smbus, with python.
I’ve done this on Raspberry Pi’s, but the tools on the duo boards are so convoluted.

Any help is appreciated.

1 Like
2

As for the bigger core, have you ever tried MicroPython / CircuitPython? It should do.

3

Thanks for the reply.
That’s interesting… is there a port of CP for the MilkV?
I use CP on all my other boards (except Raspi)… RP2040, ESP32S3, etc.
Is there a guide/documentation somewhere about porting CP or even MP onto the MilkV boards?

1 Like
4

Just try looking at this, it is probable that you will like it (but it’s not ideal).

1 Like
5

Hardware requirements
BMP280 with i2c interface.

Software requirements
python-periphery

Hardware requirements
BMP180 with i2c interface.

Hardware requirements
pcf8574x.

2 Likes
6

Thanks for the info.
Where do I get the periphery lib?
And how do I install on the duo?
Do I need to add it in build-root or can I just put into the python library?

7

I tried to import pinpong, but it failed.
Do I have use build-root to bake it into an image?

Any help on the config would be appreciated.

8

Which Duo board are you using? What firmware image are you using?

9
10

Duo256m and Duo running release SD1.1.1.
But I have the build-root SDK, so I can build what ever is necessary.

11

Milk-V Duo (64M), SD image. I built it myself against the official buildroot&SDK (v1.1.1), the only difference is no ION reserved.

Here’s pinpong, with a textbook example you could find by the link I sent earlier:

[root@milkv-duo]~# python3
Python 3.9.5 (default, Feb 13 2024, 18:09:16) 
[GCC 10.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import time
from pinpong.board import Board,Pin

Board("MILKV-DUO").begin()

led = Pin(Pin.D25, Pin.OUT)

while True:
  led.value(1)
  print("1")
  time.sleep(1)

  led.value(0)
  print("0")
  time.sleep(1)>>> 
>>> >>> milkv-duo

  __________________________________________
 |    ____  _       ____                    |
 |   / __ \(_)___  / __ \____  ____  ____ _ |
 |  / /_/ / / __ \/ /_/ / __ \/ __ \/ __ `/ |
 | / ____/ / / / / ____/ /_/ / / / / /_/ /  |
 |/_/   /_/_/ /_/_/    \____/_/ /_/\__, /   |
 |   v0.5.2  Designed by DFRobot  /____/    |
 |__________________________________________|
 
<pinpong.board.Board object at 0x3fb9233ee0>
>>> >>> >>> >>> ... ... ... ... 1
1
1
1
1
1
1
1
1
1
1
1
1
1
^Cexit_handler