1-Wire protocol implementation in Go

This is a Go port of pyDigiTemp.

Originally written in Python to replace digitemp utility in my pet project and get direct access to 1-wire devices. It was created for reading DS1820 temperature sensor connected to RS232 serial port through DS9097 adapter.

Documentation used

• Using an UART to Implement a 1-Wire Bus Master

• Book of iButton® Standards (PDF)

• DS18S20 High-Precision 1-Wire Digital Thermometer (PDF)

Supported Hardware

Bus Driver

• DS9097 - COM port adapter which performs RS-232C level conversion.

• Custom 1-wire serial port interface (see below).

1-Wire Devices Supported

• DS1820 / DS18S20 / DS1920 - High-Precision Temperature Sensor.

• DS18B20 - Programmable Resolution Temperature Sensor.

• DS1822 - Econo Temperature Sensor.

Usage

💡	See detailed examples in examples directory.

Find ROM codes for all connected devices:

import "github.com/mcsakoff/go-digitemp"

uart, _ := digitemp.NewUartAdapter("/dev/cu.usbserial-1410")
roms, _ := uart.GetConnectedROMs()
for n, rom := range roms {
    log.Printf("%d: %s\n", n, rom)
}

Get temperature from single sensor:

import "github.com/mcsakoff/go-digitemp"

uart, _ := digitemp.NewUartAdapter("/dev/cu.usbserial-1410")
sensor, _ := digitemp.NewTemperatureSensor(uart, nil, true)
temp, _ := sensor.GetTemperatureFloat()

log.Printf("%.02fºC\n", temp)

Get temperature from specific sensor:

import "github.com/mcsakoff/go-digitemp"

rom, _ := digitemp.NewROMFromString("10A75CA80208001A")
uart, _ := digitemp.NewUartAdapter("/dev/cu.usbserial-1410")
sensor, _ := digitemp.NewTemperatureSensor(uart, rom, true)
temp, _ := sensor.GetTemperatureFloat()

log.Printf("%.02fºC\n", temp)

Schematics

⚠️	IMPORTANT DISCLAIMER: All circuits presented here are collected from different sources on the Internet and thus are provided on an entirely "as-is and no guarantees" basis. I do not provide a warranty of any kind and cannot be held responsible in any manner.

1-wire serial port interface

See Serial Port Temperature Sensors - Hardware Interface for details.

USB/UART adapter

These are tested:

• Simple connect in normal mode

• Simple connect in parasitic mode

• Using diode in normal mode

• Using diode in parasitic mode

Not all schematics work in all cases, depending on an adapter and cable length.

These are not tested yet:

• Using MOSFET transistors

• .Using NPN transistors

Kudos To

• Slavko for SVG schematics and testing python version.

License

Copyright © 2020 Alexey McSakoff
Free use of this software is granted under the terms of the MIT License.

See the LICENSE file for details.