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Topic: Shield conflicts (Read 525 times) previous topic - next topic

dbvanhorn

I'm new to all this, making great progress, but I've hit a snag.

For my project, I need motor control, Bluetooth, logging to SD, and analog inputs.

I have the motor control worked out using Motor A or B on the Arduino motor shield.
I have BT comms on Serial3 working using an Ebay BT module connected to pins 14/15.
I have SD working, BUT..

It looks like SD is going to conflict with the motor.  The shield docs I have say that the SD shield needs D4, D11,D12,D13 and the Motor shield wants D3,D8,D9,D11,D12,D13, and A0,A1.

Can I just re-use the pins?  I do need SD logging while the motors are active.

If I can't re-use the pins, then what are my options?
How does one prevent pin conflicts when buying shields that seem rather sparsely documented?

Thanks!

Techone

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If I can't re-use the pins, then what are my options?


If I was you, I will keep the SD shield and pins setting as is. Only the motor control will be re-build or reconnected and posibility re-code to take into account the new pins for the motor "shield" circuit.

Quote
It looks like SD is going to conflict with the motor.  The shield docs I have say that the SD shield needs D4, D11,D12,D13 and the Motor shield wants D3,D8,D9,D11,D12,D13, and A0,A1.


SD : keep D4, D11, D12, D13 For the motor "shield" ( may be build on a new DIY board ) , use D2, D3, D5, D6, D7, D8, D9, D10 and all the analogs pins.

Sorry, that the only idea I can think of...  :smiley-roll:

dbvanhorn

:~
Oog.  I already need a 0-70vdc supply, and ideally two differential amps with high cmrr for this.  I was hoping to get farther before having to lay out a custom board.


rbhamjee

I would be curious if you ever got this up and running. I am in the exact same pickle with the motor shield and SD shield conflict.
Rather than reinvent the wheel from scratch, I'd like to know if you got this to work or have any tips on what to do (or what not to do).
Thanks.

PaulS

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How does one prevent pin conflicts when buying shields that seem rather sparsely documented?

I would think that this is rather obvious. Don't buy shields that are sparsely documented. Don't buy shields, either, that assign motor control functions to SPI pins. Boycott such shields, and they will be quickly redesigned.

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