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Topic: sainsmart 3.2 tft lcd display and a second Arduino (Read 1 time) previous topic - next topic

bobo01

Hello,

I have a Sainsmart 3.2" LCD and shield.  The shield takes up all the power pins.  I was planning on powering the LCD Arduino from another one via the vin.  Is this possible?

Thanks.

#1
Feb 20, 2013, 09:24 pm Last Edit: Feb 20, 2013, 09:31 pm by Docedison Reason: 1
yes you can power a second Arduino that way Vin to Vin and "Don't Forget the Grounds" they must be tied together too for proper operation. The 3.2 SainSmart displays work best on a Mega.. I "Think" there is one free pin besides RX0/TX0 on an Uno. I have several on Mega's and they work well. I have one displaying satellite time, barometric pressure, temp and relative humidity, something simply not possible AFAIK... on an Uno.

Bob
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

bobo01

The problem is that the shield uses the vin pin too, no idea why.  Therefore how could I use the vin pin?

Edit:  I have two Arduino Mega 2560s

#3
Feb 20, 2013, 09:54 pm Last Edit: Feb 20, 2013, 10:02 pm by Docedison Reason: 1
I used an 8 in (20 cm) 40 pin cable to extend the display pins and I pulled the pins out of the board by removing the separator plastic and first pulling the pin and then cleaning the hole and replacing all pin headers with stackable headers. (except power and I left the 40 pin connector alone)
Crossroads has another solution, he sells a Very nice screw terminal shield for the Mega. I bought one and now I seriously wonder how I got by without it.
On a similar topic Liudr sells a shield breadboard extender for the Uno that is a shield, 34 pin cable and a header to plug into a breadboard that is a real nice thing to use for extensive breadboard work... I bought one and quickly a second one and find them invaluable.

Bob
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

bobo01

Would anyone know how to bypass the shield and just connect the screen directly using wires?

#5
Feb 23, 2013, 12:57 am Last Edit: Feb 23, 2013, 12:59 am by Docedison Reason: 1
The shield for a display serves two functions the first is obvious, It provides mechanical support. The second function is not quite as apparent... The shield provides level translation from 5 to 3V3 for the logic contained in the display. As to your question, yes the shield can be replaced with wires BUT NOT THE INTERFACE COMPONENTS... I have seen many things for an "Arduino" offered for sale but never a "Jumper Kit" for "Wiring a display to an Arduino. Not Once.

Bob
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

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