Arduino Pro Mini - How to turn MISO to be used for TFT_DC?

Projects Programming
1

I have wired ILI9341 displa as attached schematic...and have problem that i want to use PIN12(MISO) for TFT_DC command so that my display can work...how can i do in arduino which command to enable sending DC command throught PIN12(MISO)?

I im using adafruit library for display and if i use PIN9 for TFT_DC it works, but i need to use MISO for that purpose because i like to have all 4 SPI ports used for TFT connection.

Here is how i define and it does not work TFT:

#define TFT_CS 10
#define TFT_DC 12

And when u define using this:

#define TFT_CS 10
#define TFT_DC 9

Then TFT works.

I know that MISO is SPI designed to read from slave SPI device, but i don't need MISO to connect to my TFT because i don't need to read TFT device ID, so i need to reuse this pin for DC (Data Command to display).

What code i need to put to Arduino IDE to make it work?

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2

I know that MISO is SPI designed to read from slave SPI device, but i don't need MISO to connect to my TFT because i don't need to read TFT device ID, so i need to reuse this pin for DC (Data Command to display).

Have you tried any other pin than the MISO ? there may be a bit more 2-way communication going on than you think.

3

Also i thought the idea of the SPI port was that you use 1 port and use CS to determine which device to communicate with (mind you conflicts with TFT screens and other devices i have seen on this forum)