1072 User Guide

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Required Hardware

  • A 1072 PhidgetSBC2
  • Sensors, LEDs, and switches to test the InterfaceKit
  • A 6-15V DC power supply
  • An ethernet cable
  • A computer

Connecting the Pieces

1072 0 Connecting The Hardware.jpg
  1. Connect any sensors to the voltage inputs on the SBC.
  2. Connect a switch or a piece of wire connecting ground to one of the digital input terminals.
  3. Connect an LED to one of the Digital Outputs by inserting the long LED wire into the digital output 0 and the shorter wire into Ground.
  4. Connect the power supply to the SBC using the barrel connector.
  5. Connect the SBC to your network with the ethernet cable. Plug the power supply into the wall outlet. The red status indicator light located near the USB ports should be lit if the unit is receiving power. The green LED located above the red LED indicates boot status. The green LED will turn on and off once during boot and then turn back on when everything is running.
  6. Other Phidgets can also be connected to the 1072 using a USB cable.


Testing Using Windows

Make sure you have the latest version of the Phidget Drivers installed on your PC. If you don't, follow these steps:

  1. Go to the quick downloads section on the Windows Page.
  2. Download and run the Phidget22 installer (32-bit or 64-bit, depending on your system)
  3. You should see the PIcon.jpg icon on the right hand corner of the task bar.

Running Phidgets Sample Programs

1072 Panel.jpg

Double clicking on the PIcon.jpg icon will start the Phidget Control Panel, which acts as an easy example launcher and will automatically detect any Phidgets plugged in to your computer. We'll use the Control Panel to ensure that the new Phidget works properly.

After double clicking on the icon, a window will open with a list of all attached Phidgets. Click on the PhidgetSBC tab, and you should see a list of PhidgetSBCs connected to your network. Double click on an SBC to bring up the configuration page in your default web browser. You can differentiate multiple SBCs by their MAC address, which is printed on a sticker on the underside of the board.

This control panel view will tell you (at the bottom):

  • The link local address of the SBC (called the mDNS address), here it is phidgetsbc.local
    • The name phidgetsbc.local is the default link local address
    • Although there is a period after the link local address in the Phidget Control panel, the address itself does not include that final period
  • The IP (Internet Protocol) address of the SBC, here it is 192.168.2.181
    • There is no default for the IP address
    • The SBC will only have an IP address if it successfully gained one through DHCP (Dynamic Host Configuration Protocol) over Ethernet

You will need one of these two pieces of information when you start working directly with the SBC Operating System for tasks such as writing and running code on the SBC, so write these down somewhere while you work through the rest of this page.

Basic Use

Basic use of the PhidgetSBC allows the opening of connected Phidgets over the network. Using another Phidget with the PhidgetSBC in this way is almost exactly like using Phidgets over USB, in respect to the API calls and behavior. However, some extra considerations need to be made when working with the Phidget Network service.

Phidget Network Service

Support for opening Phidgets over the network is made possible via the Phidget Network service. This allows a user to write an application in a system and language of their choosing and then operate Phidgets connected to the PhidgetSBC. It is a socket based server that runs on the PhidgetSBC, and allows any attached Phidgets to be seen and opened directly over the network. To use this server go to the "Phidgets->Network Service" tab in the web configuration page and enable it.

Opening and controlling a Phidget over the network is nearly the same as opening one locally. The main differences are:

  • Different open calls that include server information. New calls OpenRemote and openRemoteIP (naming depends on language).
  • Access to Network service based properties: Server hostname, port and ID.
  • Access to server connect and disconnect events, and network error events.
  • Phidgets can be opened by more then one separate application at the same time.
  • Reliability is more of a issue because network connections are easily broken

Opening a Phidget over the network is asynchronous and pervasive, just like opening locally. This means that if a connection to the remote server cannot be established right away, it will keep trying indefinitely, and even survive the server being stopped and started, etc. Instances of the Phidget Network service can be referred to either using hostname (IP Address) and port number, or by Server ID. The advantage of using a Server ID is that it stays consistent compared to IP addresses, and you don’t need to know the Port number. A Network service Server ID is assigned when the Network service is run - which on the PhidgetSBC defaults to ‘phidgetsbc’. In order to use a Server ID, the Bonjour utility also needs to be installed. Refer to the Programming Manual and the API manual for your language for more information about using the Phidget Network service.

Reliability

Determining reliability needs can become important while opening Phidgets over the network, because the network connection can potentially be interrupted at any time. This can leave the network attached Phidget in an undesirable state. For example - if a motor controller is driving a motor and the connection is lost, there is no way to stop the motor until the connection is re-established. These issues are less important if you are just receiving sensor data from an Interface Kit.

It’s generally a good idea to catch server connect and disconnect and Phidget attach and detach events in order to know the state of the connections. It’s also a good idea to catch error events - this is where network errors will be reported. If reliability is important, you should consider writing a program to run locally on the PhidgetSBC, and communicate with it through the Dictionary interface. This way, if the connection is broken, the local application will notice and be able to take any appropriate actions. See the advanced chapter for more information.

Finding Phidgets on the Network

Any Phidgets attached to the PhidgetSBC can be identified using the Status >> Phidgets page in the configuration interface, and should be seen on the network through the Network service. The Phidget Control Panel has a Bonjour tab (under Network Service >> Bonjour) that lists all detected network attached Phidgets. The Phidgets connected to the PhidgetSBC should be seen here and can be opened by double clicking its name in the menu. Network attached Phidgets can also be located programmatically with the Phidget Manager. The Phidget Manager is used with either hostname and port, or server ID, just like with ‘Open’. The manager can also be used to find all Phidgets on any Network service through Bonjour, by specifying a NULL Server ID. See your specific language’s guide for more information about coding with the Phidget Manager.

Testing Using Mac OS X

The steps are very similar to the Windows process described above:

  1. Ensure you have OS X 10.3.9 or later running.
  2. Download and run the Installer (OS software license)
  3. Click on System Preferences → Phidgets (under Other) to activate the Preference Pane
  4. Make sure that the Phidget SBC is properly attached to the network as described in the introductory video
  5. Double Click on the Phidget SBC in the Phidget Preference Pane to bring up the Web Interface in your default browser
  6. Or, click on the Bonjour tab to see attached Phidgets being run over the network and to bring up their examples

The address in the browser that connects to the SBC is either an IP address (such as 192.168.2.181) or a link local address, (such as phidgetsbc.local, which is the default). Note down the address in the browser, as you will need this information for later if you will be working directly with the SBC to perform tasks such as writing or running code. But for now, with the web interface open, we have a section to walk you through it.

Using Linux

With Linux, you have many setup options, but all involve knowing the IP address or link local address of the SBC after you have plugged it in as described in introductory video. The IP address can be somewhat difficult to obtain, but the default link local address for all new Phidget SBCs is phidgetsbc.local - which is an mDNS address. Wait at least three minutes after booting the SBC to make sure link local addressing is started. You'll also need some form of mDNS (either avahi or mDNSResponder) installed on your main computer. The avahi service is usually installed by default on most Linux machines, try which avahi-resolve to make sure. Then, try typing phidgetsbc.local into a web browser. The web interface should come up, starting with the Set the Password screen.

Note that some browsers (i.e. Google Chrome) combine search and addressing in the same address bar, so you may need to turn off Network service and prediction service in Preferences → Under The Bonnet for Chrome to treat phidgetsbc.local like a web address rather than a search term. If these steps do not bring you to the initial setup password screen as shown in the SBC Web Interface section, you will probably need to read the internet setup section on the SBC OS Page. That section contains more than just troubleshooting information - it includes in-depth information on how the SBC starts its network, your initial network configuration options, and how to connect to the SBC without mDNS using both DHCP and static IP.

If you want to use the SBC to broadcast data from Phidgets over a network, the SBC is already automatically performing this function with its attached Interface Kit, and will also do so for any Phidgets plugged into its USB ports. If this is your sole intended use of the SBC, you can skip ahead to our example on using the attached Interface Kit.

However, the SBC is much, much more than simply a way to get data from Phidgets over a network. You can use the SBC as an external Linux computer. You'll need to set a password using the SBC web interface, and write down a network address of the SBC (phidgetsbc.local, or an IP address if you worked through the internet setup section on the SBC OS Page). But after that, if no other sections in the basic SBC web interface section apply to you (using the webcam, setting up wireless networking, or checking system parameters like memory), you can skip ahead to the OS - Phidget SBC page.

Linux - Attached Interface Kit

As soon as the SBC boots and can connect to the network (either by DHCP or by mDNS/avahi), it begins broadcasting the state of its attached InterfaceKit over the network using the Phidget Network Server. To test the InterfaceKit on your Linux computer over the network, you will need to install the Phidget libraries and the Phidget Network Server if you haven't already. (If you have used any Phidget via USB and over a network on your Linux computer, you have already done this.) This process is described on the general Linux OS page, so follow those installation instructions, with the following modifications to the Linux Network Server introduction:

  • Instead of using a localhost (127.0.0.1) address, use the the SBC's IP or link local (phidgetsbc) address,
  • Instead of using the function call openRemoteIP in your code, use the function call openRemote, and the Interface Kit serial number which is on the back of the SBC.

Note that any attached analog sensors in the black ports will not show up over the Network Server as individual Phidgets. Rather, they will show up as part of the Interface Kit, through the port number that they are attached to on the SBC board.

Technical Details

Rebooting/Resetting the PhidgetSBC

To reboot the device, quickly press the black reset button found between the USB connectors and the power terminals. Both Ethernet Port LEDs (yellow-connectivity, green-activity), and the green status LED will turn off. The reboot is done when all LEDs come back on in about 25 seconds.

To reset the firmware, press and hold the button for 10 seconds until the green status LED begins to blink, then release. Both Ethernet Port LEDs will turn off (yellow-connectivity, green-activity) for 80 seconds; the green status LED will then turn off; then all LEDs will come back on in 20 seconds. All data will be lost and the operating system will be reset to a factory state.

To boot into the Recovery / Upgrade system, hold the button for 20 seconds until the green status LED switches from blinking slowly to blinking quickly, then release. The recovery system allows for factory reset, full system upgrades and recovery of the main system.

Recovery / Upgrade System

The recovery / upgrade system is a small system from which the main system can be reset/upgraded, or recovered.

Entering the Recovery System

The recovery system can be entered in two ways.

  1. From the ‘System: Backup & Restore’ web interface page.
  2. By holding down the reset button for 20+ seconds - until the green light has switched from flashing slowly to flashing quickly.

Upgrades

Generally, you should not need to do a full system upgrade. Upgrades are meant to be performed via the package system, and Phidgets maintains it’s own package repository from which to push out updates.

Occasionally, you may wish to go back to a clean install and upgrade to the latest rootfs/kernel from Phidgets. Phidgets will not be creating these images with every release of phidget21 as we did with PhidgetSBC1, rather they will be released several times a year, as needed for major changes not easy to push out via packages.

You can also flash your own custom kernel or root filesystem image.

Factory Reset

This restores the kernel and root filesystem from backup, overwriting any changes that may have been made. This is equivalent to holding down the reset button for 10 seconds.

Recovery

If the main filesystem has been damaged/misconfigured in such a way that it won’t boot, you may be able to fix the issue / recovery important files before running a reset. The recovery system runs an SSH server that you can loginto for console access. Username/password is: root/root.

You can mount the main root filesystem with the following commands (assuming it’s not damaged):

  1. ubiattach /dev/ubi_ctrl -m 6
  2. mount -t ubifs /dev/ubi0_0 /mnt

Ports and Connectors

Numbered in the circles on the diagram:

  1. 10/100baseT Ethernet
  2. Six USB Full-Speed Ports
  3. Indicator LEDs
  4. Reboot / Reset Button
  5. Power input terminal
  6. Power input jack
  7. Eight Interface Kit Digital Inputs (Indexed 0 to 7)
  8. Eight Interface Kit Digital Outputs (Indexed 0 to 7)
  9. Eight Interface Kit Analog Inputs (Indexed 0 to 7)
A. JTAG connector, for internal testing purposes only
1072 0 Layout Top.jpg

1072 0 Layout Front.jpg

1. This Ethernet port is used for network connectivity to the PhidgetSBC. This enables access to the PhidgetSBC as well as any connected Phidgets through the Network Server. Alternatively, the USB Wireless adapter can be used for network connectivity.
2. These USB ports can be used for connecting Phidgets, Wi-Fi adapters, flash drives, webcams, USB hubs, etc.
3. These LEDs indicate the status of the PhidgetSBC. The Red LED indicates that the power supply is on and running properly. The green LED indicates boot status. The green LED will turn on and off once during boot and then turn back on when everything is running.
4. This will reboot the board if pressed once. Note that this is a forced reboot. Any user programs that were running may leave their data in a inconsistent state, but this is safe for the base system. A soft reboot can be performed remotely from the configuration interface.If held for more then 10 seconds, the red LED will start to blink and enter emergency Reset mode. Once the button is released, the onboard memory will revert to a factory-fresh state. This includes overwriting the kernel and root file system, and erasing all configuration, user data, and applications. If held for more then 20 seconds, the Recovery/Upgrade system will be booted, from which a Factory Reset/Full filesystem upgrade can be performed.
5,6. The PhidgetSBC can be powered from either the terminals or the barrel connector.
NOTE: The polarity labeled on the bottom of the board is incorrect. The correct polarity is shown in the above image.
7,8,9. The Interface Kit I/O is explained in the Interface Kit section of the manual.

Power Distribution

The 12V power supply is stepped down to 5V and distributed in the following way:

  • Each USB port has 500 mA available
  • All analog inputs share a total of 500 mA
  • The digital outputs, +5V terminals, USB controller, and pull-ups all share a total of 500 mA


Power Over Ethernet

Power over Ethernet can be used to provide both a network connection and power to a device when a power outlet is not available. This means that with the proper adapters, you can run the PhidgetSBC entirely off an Ethernet source. The PhidgetSBC does not draw power directly from a powered Ethernet line, but instead can use a setup where the power is split to a separate line again near the PhidgetSBC. The board has been tested and will work with Power Sourcing Equipment that can output 6-12VDC.

Hardware Layout

The PhidgetSBC is based around the SC32440 processor. This is an ARM-920T based microprocessor from Samsung, which runs at 400MHz. Connected to this is 64 MB of SDRAM, 512 MB of large page NAND and a 10/100baseT Ethernet controller. The microprocessor brings USB Host port is connected to a 7-port USB 1.1 Hub chip. The integrated PhidgetInterfaceKit 8/8/8 is connected to one of the hub ports, with the other 6 ports being brought out to the user.

Software Layout

The PhidgetSBC runs Debian/GNU Linux as its operating system and gets booted with U-Boot. The kernel is 2.6.x and generally kept up to date with the latest releases. The root filesystem is created using Buildroot and is mounted in a ~460MB nand partition using the UBIFS filesystem, in Read-Write mode.

Configuration data is located at ‘/etc/webif’. This is where all configuration that can be set through the website is located.

User applications are stored in ‘/usr/userapps’, each is their own directory.

The kernel is stored on bare Nand in it own 3MiB partition, in the uImage format.

Date and Time

The date and time are set using ntp (network time protocol) at boot. The ntp daemon continues to run in the background and will periodically update the clock, keeping it very close to real time.

There is a real-time clock with battery backup which will preserve date/time across reboots, power removal. The real-time clock is synced to system time during reboot/shutdown. If power is unplugged suddenly, the real-time clock may not have the correct time.

Wireless Networking System

Wireless networking is supported using the available adapter and is configured through the configuration interface.

Configuration System

The configuration system used by the website is stored in ‘/etc/webif’. These files should generally not be changed manually, but there is no reason why they could not be. It’s very easy to enter invalid data that could cause the system to behave unexpectedly or not boot.

Nand Layout

The board contains 64MB on Nand. This nand is split into 7 partitions as follows:

0: u-boot size: 256K Read Only
1: u-boot_env size: 128K Read Only
2: recovery_kernel size: 2M Read Only
3: kernel size: 3M Writable
4: flashfs size: ~3.625M Read Only
5: recovery_fs size: ~ 43M Read Only
6: rootfs size: ~ 460M Writable

The final size of flashfs/recovery_fs/rootfs depends on the image size at production, and on the number/location of bad blocks in the NAND.

U-Boot and recovery kernel and filesystem cannot be written from Linux - this is a safety measure.

Boot Process

This describes the boot process from power on.

  1. Processor loads first 4 bytes from NAND into Steppingstone and runs it.
  2. Steppingstone sets up RAM, copies u-boot from NAND into RAM and runs U-Boot.
  3. U-Boot initializes the processor, sets GPIO state, etc., copies the linux kernel into RAM, sets up the kernel command line arguments, checks that the kernel image is valid, and boots it.
  4. Linux boots, bringing up USB, Networking, NAND, etc. and then mounts the rootfs NAND partition on /.
  5. init gets run as the parents of all processes, as uses the /etc/inittab script to bring up the system. This includes mounting other filesystems, settings the hostname, and running the scripts in /etc/init.d, among other things.
  6. inittab then turns the green LED on.
  7. inittab then sets up a getty on the first serial port, ready for interfacing using the debug board.

Drivers for USB to Serial adapters

The SBC kernel contains driver support for the following USB to Serial Adapters. Please consult the kernel documentation for details into the driver support for the USB to Serial adapters.


Company Product
ConnectTech WhiteHEAT
Keyspan USA-18X, USA-28, USA-28X, USA-28XA, USA-28XB, USA-19, USA-19W, USA-19QW, USA-19QI, USA-49W, USA-49WLC
FTDI Single Port Serial Adapter
Cypress M8 CY4601 Family
Digi International AccelePort USB Serial
Belkin USB Serial Adapter F5U103
MCT USB Single Port Serial Adapter U232
Inside Out Networks Edgeport Serial Adapter
Prolific PL2303


U-Boot

U-Boot is used for setting up the processor and booting Linux, and is only accessible by the serial port. Normal users will not need to use it. If you are connected to the serial port, you will see the U-Boot prompt shortly after power up. You can view the environment variables for information on how to properly boot Linux on the PhidgetSBC.

Be very careful when modifying the u-boot partition. If it is damaged or overwritten, it is difficult to fix.

Refer to U-Boot documentation here: www.denix.de/wiki/DULG/Manual for more information on using U-Boot.

Ad-hoc Networks

The SBC can be configured as a device in an ad-hoc network.

For more information, visit the Ad-Hoc Networks page.

Known Issues

There is a known issue with the USB Hub on 1072s manufactured before 2012. You can read the article on how to fix it here.

Further Reading

Check the Phidget SBC page for more details about using the Phidget SBC.

Check the 1018 User Guide for more information about the InterfaceKit on this board.

What to do Next

  • Software Overview - Find your preferred programming language here to learn how to write your own code with Phidgets!
  • General Phidget Programming - Read this general guide to the various aspects of programming with Phidgets. Learn how to log data into a spreadsheet, use Phidgets over the network, and much more.
  • Phidget22 API - The API is a universal library of all functions and definitions for programming with Phidgets. Just select your language and device and it'll give you a complete list of all properties, methods, events, and enumerations that are at your disposal.