I have this TFT display screen and this shield for it. I'm using an arduino Mega along with these for a school project, but the issue is that the shield takes up way too many pins on my Mega. I'm down to a handful of digital I/O pins left which won't do.
My question is if all of these pins on the Touch Screen Shield are necessary because I'm only defining 9 of those pins in my code. So what do these other pins do and is there a way that I can limit the amount of pins that need to be wired to the Mega?
I would appreciate any help.
The TFT uses 20 signals. The Touch controller and SD card take about 10 signals.
So you have plenty of spare pins on a Mega. The problem is accessing them with the shield in place. Angle male header strip.
Two quick questions:
So if my code is only defining 9 total pins when I create my display and touch objects using the UTFT and URTouch libraries, then what is the purpose of all the other pins? How are they doing anything without the code telling them to?
If I'm not using an SD card, can I just not plug those pins in, or is that bad for the components?
You only specify 4 control pins for the TFT.
The 16 pins used by the data bus are not in your choice.
UTFT uses 22-37. You can't change this.
The pins used by the Touch controller can be specified.
The Adapter shield fixes all the pins anyway.
You still have all the Analog pins, several PWM, I2C and COMMS pins.
You need to check the Adapter SPI schematic. To see how to use the SPI pins.