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Is Domino compatible with the Arduino Lithium backpack shield?


#1

The name says it all… Will the lithium backpack battery shield power the Domino?


#2

The supply rates are 5V and 3,3V which is just fine. This will work, yes. You can connect the wiring to Vin.


#3

We never tested it but the power pins are the same so it should work


#4

im not sure about the VIN pin, i ordered the lithium battery pack:
http://www.liquidware.com/shop/show/BP/Lithium+Backpack
(which is the same shield shape as the fez domino)

the documentation said that you could wire it off the header (although i used the 5v holes that are closer to the battery cables on the battery board for a cleaner look). i orginally soldered to the VIN and GND on the back of the domino, which gave me power to my peripherals (GPS and LCD) but wouldnt run my program. i tested this by making a quick app that just flashed the domino’s onboard LED. Anyways it DIDNT flash the LED under battery power so i re-soldered to the 5V pins instead of the the VIN and it worked.

it will also change while powering the domino if you plug the USB cable into the battery connector instead of the domino connector. its also supposed to charge the battery if you are plugged into the domino (while the battery is set on “charge”) but im not sure if thats not working or if my battery is just already fully charged.


#5

also a pic of the connection to the battery pack (blue wire is ground, i didnt have anymore black wires)


#6

those pics were of it opened up for showing the wiring positions i used, the one below is of it closed (used small metric bolts to properly mount the battery under the fez domino) and plugged into the mini USB for charging purposes.


#7

finally, this is a pic of the fez domino running the GPS and LCD with the battery pack listed above. you can see that the only thing plugged in is the GPS and that it is showing the current GPS coordinates on the LCD (charlotte nc). it is important to note the decimal degrees are shown (giving much better accuracy than what is supplied in the GPS driver file listed on this site. I will publish that on the tinyclr.com site as soon as i have it all cleaned up.

i drove into work this morning (30 minute drive) with it running the GPS and the LCD on just the battery to test its endurance. it made it without issue. Next i am going to log the GPS coordinates and times to the USB memory and test how long the battery accually lasts (i.e. let it run out and then look at the file to see start and finish times). i will post my results.


#8

A battery operated GPS data logger…I call that sexy :slight_smile:


#9

well its actually going to include a tilt compensated compass and be mounted on an RC car chassis for point-to-point gps navigation. load the coordinates you want it to follow onto the USB memory, plug it into the Pathfinder (my project name) and hit drive and off it will go.

you guys really should market the battery pack i listed above with simple directions of how to attach it to the fez domino. i would even suggest a “FEZ mobile pack” that would include the FEZ, the lithium battery pack, and the LCD button shield. hell, you could even bundle a USB memory stick into it with tinyclr.com printed on the side.


#10

What a minute, that’s my project!! ;D

What kind of RC car are you thinking of using? Also, what kind of compass?

I’m using a Traxxas Stampede for mine. See the “RC car” thread in general discussion.


#11

i think im going to use this compass:
http://www.sparkfun.com/commerce/product_info.php?products_id=8656
(Compass Module with Tilt Compensation - HMC6343)

i tried the Parallax Hitachi HM55B Dual-Axis Compass Module when i was attempting the project with the javelin stamp (not fast enough because its single threaded), but i was going to do the tilt compensated one now because i want to make sure i have the best hardware for the problem (within reason)

i have a used RC car chassis that i plan on re-using from my attempt with the javelin stamp. my final version with that technically worked but because of the single threading ended up by overcorrecting with every re-adjustment of the heading. I cant remember what kind it was (most of the body was removed years ago, but it was a relatively inexpensive pro model (not one of the cheap kids kits)

using GPS alone doesnt work very well because the signal bounces around (a 10m radius) and will totally screw up your calculations as it bounces

chris, can you link to your rc car thread, couldnt find it, just your GWAR one with pics of the chassis


#12

Hi Wolf,

Here is the thread. I linked you to page 4, where things start getting interesting. http://www.tinyclr.com/forum/1/505/#/4/

I too have been looking at that same model of compass. Looks really good, but VERY expensive. What do you think of this one? http://www.parallax.com/Store/Sensors/CompassGPS/tabid/173/CategoryID/48/List/0/SortField/0/Level/a/ProductID/596/Default.aspx


#13

yeah that one should workfor u as long as your vehicle remains fairly flat. on my testing of the other one i used if i had it more than maybe 15 degrees off level the values would be totally off. that may mess you up if you get your vehicle off flat pavement or going up a sharp incline, i didnt want to worry about that. one of my concepts is also to use this in the water, where waves will really mess up my calculations if i dont have a tilt compensated compass.


#14

Seems that everyone has the same project in mind… Im using a Traxxas T-maxx but will eventually move up to my Traxxas nitro 4tec after I get all the bugs worked out…


#15

So, that’s three of us now? Jeez. So much for originality ::slight_smile:


#16

Update:
after initially mounting the battery ive had a lot of issues

when i started with the screen on as well as usb logging (which takes a bunch of power) and the gps receiver, the processor will regularly restart. i have also not been able to get the battery to let me know that its fully charged (supposed to have the orange light turned off when its done charging). orange light comes on but never turns off. it may be a power consumption issue but im currently using a rc car battery going into the power input barrel connector.

thats a serious battery and i can tell the difference. the screen doesnt flicker like with the backpack, and it appears to last longer without restarting. i really think that the backpack just may not be getting recharged, but i cant prove it yet.

i also rewrote the FEZ_Extensions_GPS.cs file to make it a little more what i needed with the full accuracy (including the decimal etc). it has more public methods (getDate(), getTime() etc.) if anyone wants to take a look i put it up here:
http://www25.brinkster.com/contractorwolf/fez/FEZ_Extensions_GPS.zip


#17

Please take a volt meter and try to determine if the battery gets charged and next find out what it’s voltage is when fully charged.

After you have done this, please report back :slight_smile:

[quote]i also rewrote the FEZ_Extensions_GPS.cs file to make it a little more what i needed with the full accuracy (including the decimal etc). it has more public methods (getDate(), getTime() etc.) if anyone wants to take a look i put it up here:
http://www25.brinkster.com/contractorwolf/fez/FEZ_Extensions_GPS.zip[/quote]

Please create a wiki page for it :slight_smile:


#18

Hello contractorwolf,

Sometime ago, a brought also a battery shield http://www.robotshop.com/seeedstudio-solar-charger-shield-for-arduino-5.html. This one did not work properly also.

After some testing with my scoop i found out that the output voltage was variate between 4 and 6 volt.

greetings

Niels


#19

4 to 6 v => regulate connect to the 5v line and FEZ will work. But now your 5V line is 4v to 6v so watch out for your usb devices.


#20

I know, i ordered a new on, with the voltage regulator fixed.
The problem was also that all my other stuff did not work properly also.