
ONEWIRECS
ONEWIRETIM
ONEWIREDATW
ONEWIREDATR
ONEWIREIM
ONEWIRERIS
ONEWIREMIS
ONEWIREICR
ONEWIREPP
Data/Control/Interrupt
1-Wire Bus Master Control
16 MHz PIOSC
OWIRE
OWALT
OWDMA
dma_sreq
dma_done
TO µDMA
Introduction
1501
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
1-Wire Master Module
22.1 Introduction
The 1-Wire Master module is a bidirectional serial communication interface that implements the protocol
functions of the Dallas Semiconductor 1-Wire protocol and provides both power and data over a single
wire. The 1-Wire Master module can interface with a multiple variety of slaves such as thermometers,
mixed-signal devices, memory, and authentication devices.
Features of the 1-Wire Master module include:
•
Support for standard and overdrive speeds, including a late-sample mechanism
•
Allows transfers of send, receive and bidirectional bits
•
Data size transfers of 1, 2, 3, or 4 bytes with subbyte search and enumeration support
•
Interrupt capability for transaction pacing and line error
•
Optional 2-wire support for isolated lines and high voltage use
•
Efficient transfers using the µDMA
22.2 Block Diagram
details the components of the 1-Wire Master module. The clock source for the 1-Wire Master
module is the 16-MHz precision internal oscillator (PIOSC).
Figure 22-1. 1-Wire Block Diagram