Introduction¶

CircuitPython library for DFROBOT Gravity: I2C to Dual UART Module

Note: this library only uses polled communications so it is important that your project is designed to frequently check for received data. This library is useful for communication with systems with a command/response interaction with the device. The Internal FIFO is 256 bytes long and therefore it should handle many use cases. It is for use in CircuitPython and interrupts are not supported (to my knowledge). It is possible a MicroPython version could support this and this project may be forked to support this (once the author learns more about that enviroment).

Gravity: I2C to Dual UART Module (SKU:DFR0627)

Dependencies¶

This driver depends on:

Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle or individual libraries can be installed using circup.

Installing from PyPI¶

On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally from PyPI. To install for current user:

pip install CircuitPython_DFRobot_Gravity_DRF0627_Dual_Uart

To install system-wide (this may be required in some cases):

sudo pip install CircuitPython_DFRobot_Gravity_DRF0627_Dual_Uart

To install in a virtual environment in your current project:

python -m venv TestEnviromentDirectory (Name it whatever you want)
cd TestEnviromentDirectory
pip install CircuitPython_DFRobot_Gravity_DRF0627_Dual_Uart

Installing to a Connected CircuitPython Device with Circup¶

Make sure that you have circup installed in your Python environment. Install it with the following command if necessary:

pip install circup

With circup installed and your CircuitPython device connected use the following command to install:

circup install CircuitPython_DFRobot_Gravity_DRF0627_Dual_Uart

Or the following command to update an existing version:

circup update

Usage Example¶

import time
import board
import circuitpython_dfrobot_gravity_drf0627_dual_uart as DualUart

i2c = board.I2C()


uart1 = DualUart.DFRobot_IIC_Serial(
    i2c,
    sub_uart_channel=DualUart.DFRobot_IIC_Serial.SUBUART_CHANNEL_1,
    IA1=1,
    IA0=1,
)

uart2 = DualUart.DFRobot_IIC_Serial(
    i2c,
    sub_uart_channel=DualUart.DFRobot_IIC_Serial.SUBUART_CHANNEL_2,
    IA1=1,
    IA0=1,
)

try:
    uart1.begin(9600, uart1.IIC_Serial_8N1)
    print("Opened: UART 1 ")
finally:
    pass

try:
    uart2.begin(9600, uart2.IIC_Serial_8N1)
    print("Opened: UART 2")
finally:
    pass

sendID = 1
sendDelayCount = 1

while True:
    time.sleep(0.3)
    sendDelayCount -= 1
    if sendDelayCount <= 0:
        sendDelayCount = 10
        uart1.write("From1:" + str(sendID))
        uart2.write("From2:" + str(sendID))

    if uart1 is not None:
        if uart1.available():
            s = ""
            while uart1.available():
                b = uart1.read(1)
                s += chr(b[0])
            print("<1:" + s + " len:" + str(len(s)) + ">")

    if uart2 is not None:
        if uart2.available():
            s = ""
            while uart2.available():
                b = uart2.read(1)
                s += chr(b[0])
            print("<2:" + s + " len:" + str(len(s)) + ">")

Additional connection information¶

The DRF0627 comes with a cable that allows for connection to the CircuitPython hardware using a SparkFun STEMMA QT / Qwiic Breadboard Breakout Adapter Product ID: 4527 https://www.adafruit.com/product/4527

SparkFun STEMMA QT / Qwiic Breadboard Breakout Adapter

Connections:¶

Black wire -> Stemma Ground
Red wire -> Stemma 3.3 V
Green wire -> Stemma SDA
Blue wire -> Stemma SCA

To test the connection the “t” and “R” pins can be connected together. If you tie the “T” and “R” pins between the same UART the data will echo back to you on the same port. If you tie the “T” and “R” pins from UART1 to UART 2 data will be send between the two ports.

If RS485 is desired you can use a RS485 adapter such as the “SCM TTL to RS-485 Interface Module”

IC2 Addressing:¶

There are two address dip switches A1 and A0. The standard (factory setting is both switched to “ON”)

A1 = ON,   A0 = ON  : Address 0x70-0x77
A1 = ON,   A0 = OFF : Address 0x50-0x57
A1 = OFF,  A0 = ON  : Address 0x30-0x37
A1 = OFF,  A0 = OFF : Address 0x10-0x17

Additional Documentation¶

API documentation for this library can be found on Read the Docs.

For information on building library documentation, please check out this guide.

For information on the chip used on this board (WK2132), please check out (original) WK2132_DS_CN_V011_2017_5_.pdf.

WK2132_English.pdf.

Contributing¶

Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.

Table of Contents¶

Examples

Simple test

API Reference

circuitpython_dfrobot_gravity_drf0627_dual_uart