connections

TFT Display (ILI9488) → Raspberry Pi 3B+

Main display connections (SPI):

VCC → Pin 1 or 17 (3.3V) of Raspberry Pi

GND → Pin 6, 9, 14, 20, 25, 30, 34, or 39 (GND)

CS → Pin 24 (GPIO 8, CE0 - SPI0 CS0)

RESET → Pin 22 (GPIO 25)

DC/RS → Pin 18 (GPIO 24)

SDI/MOSI → Pin 19 (GPIO 10, SPI0 MOSI)

SCK → Pin 23 (GPIO 11, SPI0 SCLK)

LED (backlight) → Pin 16 (GPIO 23) or 3.3V for always-on

SDO/MISO → Pin 21 (GPIO 9, SPI0 MISO) - optional if you don't read from display

Touchscreen connections (separate SPI):

T_CLK → Pin 23 (GPIO 11, shared with display SCK)

T_CS → Pin 26 (GPIO 7, CE1 - SPI0 CS1)

T_DIN → Pin 19 (GPIO 10, shared with MOSI)

T_DO → Pin 21 (GPIO 9, shared with MISO)

T_IRQ → Pin 11 (GPIO 17) - touch interrupt

Summary Table

Display Pin	Function	RPi Pin	RPi GPIO	Notes
VCC	Power Supply	1	3.3V	Power
GND	Ground	6	GND	Ground
CS	Chip Select	24	GPIO 8	SPI0 CE0
RESET	Reset	22	GPIO 25	Reset signal
DC/RS	Data/Command	18	GPIO 24	Control
MOSI/SDI	Data In	19	GPIO 10	SPI0 MOSI
SCK	Clock	23	GPIO 11	SPI0 SCLK
LED	Backlight	16	GPIO 23	Optional
MISO/SDO	Data Out	21	GPIO 9	SPI0 MISO
T_CLK	Touch Clock	23	GPIO 11	Shared
T_CS	Touch CS	26	GPIO 7	SPI0 CE1
T_DIN	Touch Data In	19	GPIO 10	Shared
T_DO	Touch Data Out	21	GPIO 9	Shared
T_IRQ	Touch Interrupt	11	GPIO 17	Interrupt
KiCad Implementation

To create the schematic in KiCad:

Required Components:

Male 2x20 pin connector (40 pin) for Raspberry Pi GPIO

Female connector for TFT display (typically 1x14 header or similar)

Optional 10kΩ pull-up resistors for RESET and CS

100nF decoupling capacitors between VCC and GND

PCB Traces:

Connect pins according to the table above

Use wide traces (at least 0.5mm) for VCC and GND

Ground plane on bottom layer

Group SPI traces together and keep them short to reduce interference

Design Notes:

Keep SPI signals (MOSI, MISO, SCK) close together and of similar length

Add mounting holes compatible with Raspberry Pi (distance 58mm x 49mm)

Position the display connector so it sits above the Pi when mounted