Too many Directions!

In working with the Overo COM line I have come to a revelation.... well.... more of an observation really.

My revelation is this:

There are so many more possibilities as to what can be done using the Overo COM line of computers than can be accomplished by one person!

DUH! one might say - that is obvious. What really brings it home for me is looking at the computer itself with all of the different capabilities built into it's design. This machine has so many different interfaces built into it's design Gumstix had to settle on a sub-set of the interfaces to bring out to the outside world! I suspect they would have had to make the COM board bigger if they wanted to bring all of the capabilities out from the OMAP Cortex-8 processor just because there is no physical way to have the interfaces access the outside world through the two 70-pin connectors on the current boards. Too bad as there are other interfacing capabilities on the OMAP processor that are not accessible.

OK - So now you have some idea of the quandray I face - so many possibilities, so little time! the following is a partial list (as I am sure you can come up with ideas I have not even considered) of things I want to do with this machine....

1. Intellegent firewall/router/access point.
There is no reason the machine could not handle this sort of application - it is based on Linux and there are all sorts of applications to implement a firewall/router/wireless access point using the Overo COM computer.

2. Wireless MESH-Based communications data collection & processing system.

This is one neat idea as what I envision is the COM system configured to run wireless communications between multiple COM machines and using a MESH network for redundancy of the network link. Given the computing power of the OMAP-3 processors and using the 3530 gives the ability to perform DSP based processing one should be able to come up with all sorts of monitoring/control system ideas for this computer. Heck, you can even have a display using the machine's video capabilities for such things as process control and monitoring. Talk about inexpensive control systems!

3. Intrusion Protection System.

Hmmm - How about a computer system small enough to fit in a cigarette case but able to detect unauthorized access to a network - maybe even able to thwart a hacker attack on a network too. There are software applications for linux that allow monitoring and intrusion prevention (using firewall controls) that can run on the COM machines. At 600-MHz the COM machines clock is faster than a Cisco PIX-515 firewall if that gives you any idea of the capabilities. I know - this is an ARM based RISC machine - so what - it is still FAST! (grin).

4. Intertial Navigation System.

This is an interesting idea I had. There is enough compute power and interfacing capabilities in the COM machines to build an inertial Navagation system! At first I thought it would cost an arm and leg to build such a device as the cheapest one I could find on the Internet runs more than $4000 USD. Well - a little research reveals you can obtain the hardware for a GPS, 3-Axis Magnatometer capable of very low magnetic field measurements down to 0.015 u-Tesla and a 6-degree of freedom solid-state gyro/accellerometer package for less than around $200 - $250 USD! Given the Earth's magnetic field ranges from around 30 - 60 u-Tesla there is no problem in detecting the direction/orientation of the Earth's magnetic field! With a GPS, Magnatometer and gyro/accellerometer package you can build your own inertial navigation system that rivals most expensive packages for a small fraction of the cost. What can you do with such a system??? How about sailboat autopilot? UAV anyone?

5. Magnatometer Mapping System.
Building upon the inertial Navigation System you could use the 3-axis magnatometer output along with the GPS information to produce a map of the magnetic field in an area - by moving back and forth along a line and sweeping the area and given you know the orientation and direction of movement based on the sensor inputs from all of the sensors and GPS you can draw a "map" of the earth's local magnetic field strength and orientation relative to the sensing system over a given area. Basically you have a method to detect iron/steel objects by the affect they have on the local magnetic field. Buried treasure anyone???

6. Perimeter Monitoring System.

An interesting thought here. Why not use the COM machine as a perimeter monitoring system. Since you can get a LCD display for the COM machine you could actually "draw" the perimeter you are monitoring on the display then change icons/colors to denote where things are happening. By using wireless sensors and coupling back to the COM using wireless communications you could actually deploy a monitoring system rather quickly. I am not delving too much into the details here but there are all sorts of possiblities!

7. Home Entertainment System.
I follow several forums such as the Gumstix and Beagle-Board Forums and I get this idea from the Beagle-Board forum. Seems there is an effort out to build a home entertainment system based on the linux operating system. This would be a natural thing for the COM computer as it runs linux. The really nice thing is the Gumstix Overo line and the Beagle-Board both use the same OMAP processor (at least the OMAP 3530) so the same applications software will run on both boards. Granted there may be some small differences but for the most part there is very little difference as far as applications software is concerned. One such application is a home entertainment system - it is in development on the Beagle-Board so should port directly over to the Overo COM machines too (grin).


8. Home Control/Monitoring System.

This idea is a combination of the perimeter monitoring system and the home entertainment system. Why not combine them to have a total home control and monitoring system - you would use the television as the display for the system when you needed to check on it and then could watch movies played through the COM board or TV from an external source. All you have to do is use your imagination to come up with all sorts of possiblities!

As you can see I am having a great time coming up with ideas - now all I need is the time to work on them! Hopefully in the coming months I will actually have the time to put into implementing some of the ideas mentioned here. As I work my way through them I plan to post the information here so others may follow along and hopefully make some improvements on my initial implementations! That is what public domain software/hardware is all about - improving upon ideas! Everybody comes out ahead!!!

I thought of some more ideas and have listed them below but did not expand on them - see what you can come up with for them and let us know! Who knows - you may come up with the next killer application!!!

9. Network Monitoring System.

10. Communications System.

11. VoIP PBX System.

Your Ideas here.

As you can see - If you can dream it you can do it! All it takes is just some common sense and a will to succeed. It also helps if you have an understanding of the projects and know where to find the parts. Comments??? Ideas??? Let me know!!!

Does Size Matter - You Bet It Does!

OK - I guess the title could be read as "something" from a certain type of "Television Commercial" but I could not resist!

The Overo Earth, mounted on the Summit Expansion board is still a very small computer system. If you don't believe this statement then take a look at the picture to the right!

Yes - that is an American Quarter and that is a Double-A (AA) Ni-Cad battery below the board.

If you look real close you can make out the outline of the actual Overo Earth board - it is just below the 40-pin holes under the Quarter and above the audio, HDMI, USB Host connectors on the Summit Expansion board.

The configuration shown in the picture is the most likely one most hobbiests or experimenters will use. You don't have to have "Leet" soldering skills or Microscopic Vision to build and solder the 70-pin connectors to access most of the capabilities of the Overo Earth computer - and - as a bonus you have video, audio, USB and console access directly off the Summit Expansion board - not to mention you don't have to build power conversion circuits for the 3.3-VDC/1.8-VDC power supplies needed to run the Overo Earth computer. For the price the Summit Expansion board is well worth it - just in the reduction of the "frustration factor" alone.

If you decide to access some of the more interesting interfaces, such as the SPI, I2C, 1-wire, PWM, ADC and the rest of the input/output connections brought off the Overo Earth computer you will need to keep the following points in mind:

1. All of the voltages to the different interfaces are 1.8-VDC. If you exceed this by very much you probably will let the "magic smoke" out of the Overo Earth OMAP-3503 integrated circuit as most of the interface connections go directly to the integrated cirtcuit.
   ( I will be describing a method to "translate" the 1.8-VDC logic levels to something more in line with current inexpensive sensor technologies - read: 3.3 - 5.0 VDC in a later blog entry)
   
   
2. You will need to supply the power externally to any interface devices you want to connect to the Overo Earth computer interfaces - the Overo Earth computer does not have the additional power capacity to run very many sensors, if any at all. The on-board power regulator does not have much additional reserve power capacity so it would be wise to power external sensors with an external power source.
   
   
3. If you decide to put a socket in the 40-pin holes on the Summit Expansion board instead of soldering wires directly to the hole locations put the socket on the BOTTOM side of the expansion board. The reason for the bottom placement location is to allow you access to the micro-SD location without requiring the removal of the Overo Earth computer from the Summit Expansion board. The 70-pin connector connections are pretty fragile and each time you remove and insert the Overo Earth on the Summit Expansion board you run a risk of damaging one or both 70-pin connectors. Better safe than sorry!

Overo Connections - reaching the outside world....

While the Overo Earth computer, in it's present form, has a great potential for all sorts of applications it has a "minor" drawback... Very little in the way of outside communications! While the computer has two 70-pin connectors with all sorts of input and output capabilities most, with the exception of companies with the skilled workforce, will have problems connecting to the computer!

To aleviate this problem Gumstix has an expansion board the Overo Earth plugs into that brings all sorts of connectivity to the miniscule computer board - Enter the Summit Expansion Board.

As you can see from the image to the right there are several connecitons available on the expansion board that allow you to access different aspects of the Overo Earth computer:

Features:

1. USB OTG mini-AB


2. USB host mini-A (experimental)


3. DVI-D (HDMI) video out


4. Audio In / Audio Out (stereo)


5. USB Serial Console


6. 40-Pin connector location on board
   (Signals available on 0.100-inch through-holes at 1.8V logic levels)

• Two (2) two-wire serial ports


• One 1-wire port


• 6-ea. PWM output lines


• I2C port


• SPI Bus


• 6 ea. A/D lines (at 1.8-V logic)


• processor control signal lines.
  

Power: 4V to 5.5V input

Connectors: 2-ea. 70-pin AVX 5602-24 connectors
(interface to Overo Earth board)

Size: 80mm x 39mm

Mounting: Four (4) x #2 mounting holes

Points of Interest:

1. As delivered the Overo Earth/Summit USB-OTG port is configured as a host port - you will need either a mini-A USB to mini-B cable (available from Gumstix for a reasonable price) or you will need to perform a modification (add a jumper) to the USB-OTG port. If you have really good soldering skills (the connector pins are really small!) you can put a solder bridge between pin-4 and pin-5 on the circuit board side of the USB-OTG connector to fool the computer into detecting a mini-A connector when you have a mini-B connector plugged into the USB-OTG port (this is exactly what the mini-A connector does). Personally I think it is better to just spend the small amount of money and order the correct cable - and if you plan to use the USB Host connection you will need a mini-A to mini-B cable anyway as the USB Host connector is designed for mini-A USB connector ONLY.
   


2. While the video output port is labeled "HDMI" and the Overo Earth is capable of HD-720P the factory configuration is currently 1024 X 768. If you want a different resolution you will need to setup a development environment and recompile the kernel to make the change to a different display resolution. If you don't have a monitor which supports DVI-D (or HDTV) then you will need to get a DVI-D to RGB converter to see the display.
   


3. The USB Console port is just that - the console connection to access the Overo Earth operating system during bootup or as a local terminal. In the Linux/Unix world there is a "console" that can be seperate from the normal display, and usually is. This allows debugging and initial configuration or configuration changes without the need for the system to be booted completely up where the connected keyboard, mouse and or display may not be active yet. Normally you don't need to have a "console" connected but it sure can come in handy if there is no other way to communicate with the system (provided the operating system is running and recognizes the console). During the bootup process messages are printed to the console so this port is very handy during bootup troubleshooting.

So Little Info - So Much Capability!

The Overo Earth by Gumstix is a very powerful, and VERY small computer capable of performing a great many tasks - if you know how to use it!

My reasons for building this blog about the device are two-fold.

1. I needed a "place" to put information as I found it that would be rather safe and easy to access (beats doing backups all the time and I tend to reformat things a lot).

2. I wanted to "share" the information with anyone interested in it. From the discussions I have seen on some of the mailing lists dealing with the Gumstix machines I thought this would be a pretty good way of sharing the information.

As I find information I will be posting it here. Hopefully you will find it helpful or at least entertaining.

Now, one thing that should be pretty apparent is the Overo Earth computer does not have any obvious interfaces available to allow you to see the display (neither a console or video display), any form of recognizable connectors to allow you to connect a keyboard or mouse to the unit, nor any form of additional connectors for such things as USB or audio (microphone or headphone/speaker). Hmmm - all of that is actually available, but not in the "form" you are used to seeing! If you look real close at the picture you will notice two connectors on the bottom of the circuit board. Each connector is a 70-pin connector with all sorts of input/output connections to the computer system.

I know - you are probably thinking you have to fire up the ole soldering iron (micro-tip please), get out the microscope (these pins are REALLY REALLY SMALL!) and make an interface board just so you can use the computer. Well, you can do all of that if you want to but I am basically lazy and the ole eyes are not what they used to be! You can purchase an expansion board from Gumstix which already has the different interfaces built on-board and is also configured with a 5-VDC power supply that converts the 5-VDC to the 3.3-VDC needed to power the Overo Earth board. The Overo board has it's own 3.3-VDC to 1.8-VDC triple-converter built directly on the Overo Earth board but requires only 3.3-VDC to operate. More on this in a following posting as this is the key to allowing low-power operation that extends battery life.


The expansion board is called the Summit Expansion board and is directly available from Gumstix, the same folks who build the Overo Earth computer.