Minimum wiring for remote ST7735R SPI TFT display
According to the Adfruit 1.8&quot; TFT display (which is an enhanced version of my display) documentation I can't reduce my cable to four wires.

This color display uses SPI to receive image data. That means you need at least 4 pins - clock, data in, tft cs and d/c. If
you'd like to have SD card usage too, add another 2 pins - data out and card cs. However, there's a couple other pins
you may want to use, lets go thru them all!



SCLK - this is the SPI clock input pin. Required.
MOSI (DIN / SDA) - this is the SPI Microcontroller Out Serial In pin, it is used to send data from the microcontroller to the SD. Required.
card and/or TFT. Required.
Card CS - this is the SD card chip select, used if you want to read from the SD card. Not required and can be grounded.
D/C (Data Command) - this is the TFT SPI data or command selector pin. Required.
RST - this is the TFT reset pin. Connect to ground to reset the TFT! Its best to have this pin controlled by the
library so the display is reset cleanly, but you can also connect it to the Arduino Reset pin, which works for most
cases. Required but maybe possible to use a local RC delay.
Vcc - this is the power pin. Required.
GND Required.


As far as I can see I need a minimum of six wires between my micro and the display so I can't use an industrial M8 connector as I hoped.
I'll go with a local Nano at the display and this only requires VCC, GND and serial in.