Maxim Integrated MAXREFDES132 User manual

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System Board 6304
MAXREFDES132#: 1-Wire Shield
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MAXREFDES132#providesaconvenientplatformforinterfacingwith1‐Wire
®
devices,1‐WireEvaluation
Kits(EVkits),andiButton
®
devicesusingtheDS2484I
2
C‐to‐1‐Wiremaster,orabit‐bangmasteronD2of
theArduinoform‐factorpinout.
Features
 DS24841‐Wiremaster
 F5iButtonsocket
 6P6CRJ‐11jack
 mbed.orglibraryandArduinolibraries
 Arduino
®
shieldformfactor
Competitive Advantages
 Portable
 Compact
 Flexible
 Costeffective

Applications
 1‐WireNetwork
 DataLogging
 RapidPrototyping
Introduction
Maxim’s 1-Wire bus continues to flourish in the era of IoT. This unique protocol provides
communication and power along a single wire, at relatively long distances. Now, with
MAXREFDES132#, Maxim merges a reliable, hardware based 1-Wire master with Arduino and
mbed.org platforms.
MAXREFDES132# provides a convenient platform for interfacing with 1-Wire devices, 1-Wire
EV kits, and iButton through the DS2484 I
2
C-to-1-Wire master, or a bit-bang master on D2 of
the Arduino form-factor pinout. Both masters are supported by the ARM
®
mbed
™
OneWire
Library and the Arduino Library. Bit Banging is only supported on the MAX32600MBED
platform, the DS2484 I
2
C-to-1-Wire master can be used on any mbed platform.
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SystemDiagram
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Figure1.TheMAXREFDES132#referencedesignblockdiagram.
Detailed Circuit Description
Figure 1 is a block diagram of MAXREFDES132#.
The MAX3394E two-channel bidirectional level-translator provides compatibility between 5V
and 3.3V platforms using the IOREF pin of the Arduino form factor.
The DS2484 I
2
C-to-1-Wire master provides internal user-adjustable timers that relieve the
system host processor from generating time-critical 1-Wire waveforms, supporting both standard
and overdrive 1-Wire communication speeds. In addition, the 1-Wire bus can be powered down
under software control through D3 of the Arduino form-factor pinout.

D2 can be used to bit bang the 1-Wire bus by installing JP1 on pins 1-2 and installing JP2 to
connect the provided pullup to the bus. Bit Banging is only supported by the OneWire Library on
mbed for the MAX32600MBED board.
Detailed Description of Firmware
A OneWire Library that supports all of our silicon masters from one common API has been
developed for ARM Cortex
®
-M micros using the online development environment mbed.org.
The library and example programs can be found at the following links.
https://www.mbed.com/en/
 mbed.org
o Libraryhttps://developer.mbed.org/teams/Maxim‐Integrated/code/OneWire/
o DemoProgramhttps://developer.mbed.org/teams/Maxim‐
Integrated/code/MAXREFDES132_OneWire_Demo/
 Arduino
o Libraryhttps://github.com/MaximIntegratedRefDesTeam/OneWire
o ExampleprogramsforArduinocanbefoundinthelibrarydownloadfolder
OneWire/examples
The demo program iterates through the devices on the 1-Wire bus, and prints their 64-bit ROM
IDs to a terminal. If the DS1920 is found, a temperature conversion is executed and the
temperature is displayed in the terminal.
Figure 2. Demo program flow chart.

Quick Start
Required equipment:
Windows®PCwithaUSBport
MAXREFDES132#
CompatibleArduinoform‐factormbedplatform
Procedure
The reference design is fully assembled and tested. Follow the steps below to verify board
operation.
mbed.org
1. ConnectMAXREFDES132#toyourplatform.
2. EnsureJP1andJP2areconfiguredproperlyforthe1‐Wiremasteryouwouldliketouse.
1. DS2484:JP1onpins2‐3,JP2removed.
2. BitBang:JP1onpins1‐2,JP2installed.BitBangisonlysupportedonMAX32600MBED
platform.
3. InstalltheprovidedDS1920iButton,orusersupplied1‐Wiredevice.
4. ConnectUSBcablefromthePCtoyourplatform.
5. Ifyouhaveneverusedmbed,setupanaccountandaddyourplatformtoyouronlinecompiler
accordingtotheinstructionsonyourplatform'sproductpage.
6. IfyouareusingWindowsandhaveneverusedserialcommunicationsbetweenyourPCandyour
mbedplatform,followtheinstructions.https://developer.mbed.org/handbook/Windows‐
serial‐configuration
7. Navigateyourbrowsertothefollowinglink.https://developer.mbed.org/teams/Maxim‐
Integrated/code/MAXREFDES132_OneWire_Demo/
8. Clickthe'Importthisprogram'buttonandimportthedemoasa'program'
9. Ensurethatthe#defineforthe1‐Wiremasteryouwanttouseisuncommentedandallothers
commentedout
10. Compileanddownloadtheresultingbinarytoyourplatform.
11. OpenHyperterminal,oryourfavoriteterminalemulatortofindtheappropriateCOMportfor
yourplatform,andconfiguretheconnectionfor9600bps,8‐N‐1withnoflowcontrol.
12. Ensuretheterminalisconfiguredfor'Auto'receiveand'CR+LF'transmit.
13. Presstheresetbuttononyourplatformandexercisethedemo.
Arduino
1. DownloadtheOneWireLibraryandinstallittoyourlibrariesfolderfollowingthedirections.
https://github.com/MaximIntegratedRefDesTeam/OneWire
https://www.arduino.cc/en/Guide/Libraries
2. ConnectMAXREFDES132#toyourArduinoboard.
3. EnsureJP1andJP2areconfiguredproperlyforthe1‐Wiremasteryouwouldliketouse
1. DS2484–JP1onpins2‐3,JP2removed
2. Bit‐Bangmaster–JP1onpins1‐2,JP2installed.

4. InstalltheprovidedDS1920iButton,orusersupplied1‐Wiredevice
5. ConnectUSBcablefromthePCtoyourArduinoboard.
6. EnsurethatyouhavetheCOMportthatyourArduinoboardisconnectedtoselectedinthe
ArduinoIDE.
7. DownloadtheexampleprogramtoyourArduinoboardandopentheSerialterminal.
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1‐WireisaregisteredtrademarkofMaximIntegratedProducts,Inc.
ArduinoisaregisteredtrademarkofArduinoLLC.
ARM,Cortex,andmbedareregisteredtrademarksofARMHoldings.
iButtonisaregisteredtrademarkofMaximIntegratedProducts,Inc.
WindowsisaregisteredtrademarkandregisteredservicemarkofMicrosoftCorporation.
© 2017 Maxim Integrated