1 Wire Pi
1 Wire Pi expansion board legacy information
Created: 11/05/2016 | Last Updated: 02/02/2019
This item has been replaced with the 1 Wire Pi Plus.
- 1-Wire® to I2C host interface with ESD protection diode.
- Stackable with other Raspberry Pi accessory boards.
- Buffered 5V I2C port.
- External 5V power input for 1-Wire® interface.
The 1 Wire Pi from AB Electronics UK is a communication board supporting the 1-Wire® protocol. A 5V buffered I2C port is also provided on the board.
The 1-Wire® port is based around a DS2482-100 I2C to 1-Wire® bridge device. The DS2482-100 provides bi-directional protocol conversion between the I2C port on the Raspberry Pi and any attached 1-Wire® slave devices. An ESD Protection Diode is used to protect the 1 Wire Pi and Raspberry Pi from electrostatic spikes on the 1-Wire® port. Connections to the 1-Wire® port can be made through the RJ-12 socket or the solder points on the PCB. See our KB page for configuring and using the 1-Wire® port on your Raspberry Pi.
A 5V input port is also provided allowing you to use an external power supply on the 1-Wire® interface, reducing the load on the Raspberry Pi. If you choose to use the external 5V input please remove the jumper on the board to isolate the Raspberry Pi 5V bus.
A detailed tutorial has been written by Jack Creasey, author of Raspberry Pi Essentials,for the setup of OWFS with the 1 Wire Pi and 1 Wire Plus boards. View the tutorial.
1-Wire Pi Datasheet
DS2482S (1-Wire Interface)
Input Ratings & Specifications
Vdd (5V input pin): 5.0V
Maximum current on 1-Wire pins: ±20 mA
I2C SDA/SCL voltage: 5.0 V
I2C port current: 100 mA
Click to download schematic PDF.
Click image to enlarge
The Quick2wire lib from https://github.com/quick2wire/quick2wire-python-api allows easy access to the I2C port via Python.
Configuring and using the 1-Wire® port on your Raspberry Pi
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