Stacking shields on an UNO

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LePaul
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Stacking shields on an UNO

Post by LePaul »

Good day!

For reference, I am following the model of this wonderful tutorial (https://learn.adafruit.com/bluetooth-mo ... r/hardware)

Now...here's the twist...

I have the Adafruit Motor/Stepper/Servo Shield for Arduino v2 Kit - v2.3 and have stacked the Adafruit 16-Channel 12-bit PWM/Servo Shield - I2C interface on top (since you need the access the servo connectors on top!) On the Servo shield I have Address = 0x41 Offset = binary 00001 set (Each board in the chain must be assigned a unique address.) All set.

Now...I want to use the Bluetooth (Adafruit Bluefruit LE SPI Friend - Bluetooth Low Energy (BLE) )...well, I COULD put it on the motor shield, like the original tutorial. BUT...will it being sandwiched under the Servo Shield be a problem?

OR...should I put it on the Servo Shield and just reference the different address?

I wasn't sure how much interference would occur with the BLE being below another board?

Thanks!
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Re: Stacking shields on an UNO

Post by Amedee »

I first thought you wanted to stack UMO's...

Anyway, since I'm here...
I have no experience with I2C, but it is a bus, so it does not really matter where you put it (of course with a different address)
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Re: Stacking shields on an UNO

Post by LePaul »

I'm really curious of there's a lot of interference if I sandwich the bluetooth transmitter below another shield.
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Re: Stacking shields on an UNO

Post by ivan.akapulko »

BT shield has pins for external antenna? If yes, it may solve all the problems.
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Re: Stacking shields on an UNO

Post by LePaul »

Not really an option on this fella

https://www.adafruit.com/products/2479

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Re: Stacking shields on an UNO

Post by ivan.akapulko »

according to the datasheet, square white element at the top of the Board is the antenna. Thus it is possible to unsolder and replace with something else. Thus solving the problem.
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Re: Stacking shields on an UNO

Post by LePaul »

Really? I wonder what...never thought about that
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Re: Stacking shields on an UNO

Post by ivan.akapulko »

Look at page 22 in datasheet, there is a photo of unsoldered antenna with some specs
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Re: Stacking shields on an UNO

Post by ivan.akapulko »

Here is something about external antennas: http://web.archive.org/web/200810171844 ... dboardHorn
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Re: Stacking shields on an UNO

Post by ivan.akapulko »

Have reason googling about log periodic antennas. I can' find any online calculator for this in native english, but here is translation from russian. Hope, it helps.
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Re: Stacking shields on an UNO

Post by Amedee »

Hmmmm!

I think you are trying to boil the ocean here...

Just use the KISS principle -- while it might work in difficult conditions, the best for an antenna is line of sight don't try to make it more complicated.

Also, from your first post I though it was a SPI device, but you link to a FTDI/Serial one...
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Re: Stacking shields on an UNO

Post by LePaul »

Well this assembly will be inside R2's dome, so that shortens the range too. The xbox controller works despite the hub sitting inside R2's body
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Re: Stacking shields on an UNO

Post by ivan.akapulko »

I decided that Paul is trying to implement a project controllable camera for shooting. It was initially unknown what distance he needs. If all of this will be used inside the droid, you can not be afraid of interference , I think. it's too small distances to the original sandwich was on something to influence.
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Re: Stacking shields on an UNO

Post by LePaul »

No, actually my goal is for this blue tooth enabled controller to extend and retract R2-D2's periscope in and out of his head.

I would like to figure out how to mount my Asus Nexus 7 onto my Spektrum DX6 remote and use the tablet as a means to help control his gadgets :)
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Re: Stacking shields on an UNO

Post by ivan.akapulko »

LePaul wrote:No, actually my goal is for this blue tooth enabled controller to extend and retract R2-D2's periscope in and out of his head.

I would like to figure out how to mount my Asus Nexus 7 onto my Spektrum DX6 remote and use the tablet as a means to help control his gadgets :)
Well, in this case, simply solder the Bluetooth module is not on the pins but on the cable length you need.
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