Maxim Integrated MAXREFDES131 User manual

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System Board 6331
MAXREFDES131#: 1-WIRE GRID-EYE SENSOR
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MAXREFDES131# is a sensing solution featuring the Panasonic AMG8833 Grid-EYE®
and the Maxim 1-Wire®bus, enabled by the DS28E17. The system enables presence
sensing, people counting, and gestures while tethered up to 100m along the 1-Wire bus.
The board features RJ-11 connectors and convenient mounting holes for quick
evaluation and implementation.
Example source code for interfacing with MAXREFDES131# is available for both Arm®
mbed™and Arduino®platforms. This design conveniently works with MAXREFDES132#,
a hardware 1-Wire shield. A demonstration GUI allows for visual feedback of up to 10
daisy-chained MAXREFDES131# 1-Wire Grid-EYE sensors.
As with all Maxim reference designs, the BOM, schematics, layout files, and fab files are
all available from the Design Resources tab. In addition, boards are available for
purchase.
Features
1-Wire network
Flexible location
Sleep mode
Example source code
Demonstration GUI
Competitive Advantages
Extended range
Compact
Power-conserving sleep mode
Cost effective

Applications
Building automation
People counting
Lighting control
Presence sensing
Gestures
Introduction
The future of smart connected devices is bright; however, many of the distinct
applications are unclear and waiting to be invented. Clearly, critical components of IoT
applications will ensure the safety of people and buildings, movement of commerce, and
activation of features. For these reason, MAXREFDES131# is the future of IoT. This
unique system marries a high-performance passive IR-sensing array, Panasonic’s Grid-
EYE, with Maxim’s 1-Wire bus, for enhanced range and simple interface.
MAXREFDES131# integrates the DS28E17 1-Wire-to-I2C master bridge with the
AMG8833 Grid-EYE sensor from Panasonic electronic components. This architecture
allows the sensor to be placed up to 100m from the host processor, on the 1-Wire bus.
The DS2413 1-Wire dual-channel addressable switch along with the MAX4717 dual-
SPDT analog switch allow enumeration of units on the 1-Wire bus. In addition, all units
can be put to sleep, or individually selected once enumerated, reducing power
consumption.
Example source code for interfacing with MAXREFDES131# has been developed for
both mbed and Arduino platforms. A demonstration GUI has also been developed
allowing for visual feedback of up to 10 daisy-chained MAXREFDES131# 1-Wire Grid-
EYE sensors.
Detailed Description of Hardware
Figure 1 provides a block diagram of MAXREFDES131#.
The design features two RJ-11 jacks, H1 and H2, for interfacing to the hardware and
daisy chaining units together. At power up, the MAX4717 comes up with COM1
disconnected from the 1-Wire bus and COM2 connected allowing the host to see the
first DS28E17 on the bus.
The DS2413 allows the host to connect/disconnect downstream units of daisy-chained
MAXREFDES131# units. In addition, the DS2413 channel controlling the connection of
COM2 to the 1-Wire bus also puts the DS28E17 to sleep when COM2 is disconnected
from the 1-Wire bus. When the DS28E17 is put to sleep, it disconnects power from the
AMG8833 reducing the current consumption of a single MAXREFDES131 from ~8mA to
~0.5mA. The I2C bus of the DS28E17 1-Wire-to-I2C master is also connected to H2 of
each MAXREFDES131#.

Figure 1. Block diagram of MAXREFDES131#.
Detailed Description of Software and Firmware
A demonstration GUI and corresponding firmware showcase the interface to and
operation of multiple MAXREFDES131# units, daisy chained together. The GUI works
on both mbed.org and Arduino platforms. Figure 2 provides a flow chart for the
operation of the GUI.
The GUI starts by initializing all controls and enumerating available COM ports. The
system disables all controls, except for the “COM Port List” dropdown. Once the user
selects a COM port and the firmware responds, the “Enumerate Sensors” push button is
enabled.
After the user presses the “Enumerate Sensors” button, the firmware responds with a
message containing the number of MAXREFDES131# units attached to the 1-Wire bus.
In addition, the “Select Sensor” dropdown will be enabled.
After the user selects a sensor from the dropdown list, the “Receive Data” push button
will be enabled. Once the “Receive Data” push button is pressed, the firmware will start
sending data to the demonstration program, all other controls are disabled until the
“Stop Receiving Data” push button is pressed.

Figure 3 provides a flow chart for the operation of the firmware.
The firmware consists of an interrupt service routine (ISR) that receives commands from
the demonstration GUI and sets the demo state based on those commands. A switch
statement in the main loop evaluates the state.
Figure 2. MAXREFDES131 GUI flowchart.
Figure 3. MAXREFDES131 Firmware flowchart.

Quick Start
Required equipment:
 MAXREFDES130#, MAXREFDES132#, or equivalent 1-Wire hardware interface.
For Arduino, this interface must use the DS2484 I2C-to-1-Wire master.
 MAXREFDES131#
 mbed or Arduino platform and appropriate USB cable
 PC with USB interface
Procedure
 Download MAXREFDES131DemoV1.00.zip.
 Extract the zip file to the desired location on your PC.
mbed.org
1. Connect MAXREFDES130#, MAXREFDES132#, or equivalent 1-Wire hardware
interface, to your platform board.
2. When using MAXREFDES132#, 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. Software master – JP1 on pins 1-2, JP2 installed.
3. Connect USB cable from the PC to your platform.
4. If you have never used mbed, please set up an account and add your platform to
your online compiler per the instructions on your platform’s product page.
5. If you are using Windows® and have never used serial communications between
your PC and your mbed platform, please follow the instructions here.
6. Navigate your browser to the following link.
7. Click the “Import this program” button and import the demo as a “program”
8. In the file maxrefdes131_demo.h you can select the desired master for your
configuration.
Figure 4. Master selection for mbed demo program.
1. Compile and download the resulting binary to your platform.
2. Connect MAXREFDES131# to the 1-Wire bus with the provided cable.
3. Reset the mbed platform.
4. Navigate to where you installed the MAXREFDES131DemoV1.00 folder.
5. Double click on the .exe file in the folder and exercise the GUI.

Arduino
1. Download the OneWire Library and install it to your libraries folder following the
directions.
2. Download the OWGrid-EYE Library (1-Wire Grid-EYE) and install it to your libraries
folder using the same directions as in step 1.
3. Connect MAXREFDES130#, MAXREFDES132#, or equivalent 1-Wire hardware
interface, to your Arduino board.
4. If using MAXREFDES132#, ensure JP1 is on pins 2-3 and JP2 is removed.
5. Connect USB cable from the PC to your Arduino board.
6. Ensure that you have the proper COM port selected in the Arduino IDE “Tools”
menu.
7. Download the example program “MAXREFDES131_GUI_Firmware” found under
the ”1-Wire Grid-EYE” library to your Arduino.
8. Reset your Arduino.
9. Navigate to where you installed the MAXREFDES131DemoV1.00 folder.
10.Double click on the .exe file in the folder and exercise the GUI
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1-Wire is a registered trademark of Maxim Integrated Products, Inc.
Arduino is a registered trademark of Arduino LLC.
ARM and mbed are registered trademarks of ARM Holdings.
Grid-EYE is a registered trademark of Panasonic Corporation.
Windows is a registered trademark and registered service mark of Microsoft Corporation.
©2017MaximIntegrated