Unit PiTFT35

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Description

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Adafruit PiTFT 3.5" LCD Driver unit

The Adafruit PiTFT 3.5" LCD is a 480 x 320 pixel TFT with resistive touchscreen using a Himax HX8357 driver and a STMicroelectronics STMPE811 resistive touchscreen controller.

This unit ties together the various components needed to make one of these boards work with Ultibo by finding the correct SPI device, creating the STMPE811 Touch device, creating the HX8357D Framebuffer device and registering all of it with the correct parameters for the Adafruit board.

Details:

HX8357D

Width: 320

Height: 480

SPI Mode: 0

SPI Frequency: 42000000

SPI Chip Select: SPI_CS_0

DC GPIO: GPIO_PIN_25 (Pull: GPIO_PULL_NONE)

RST GPIO: GPIO_PIN_UNKNOWN

Backlight GPIO:

GPIO_PIN_2 (STMPE GPIO)

GPIO_PIN_18 (PWM)

STMPE

Chip: STMPE_CHIP_610

SPI Mode: 0

SPI Frequency: 500000

SPI Chip Select: SPI_CS_1

IRQ GPIO: GPIO_PIN_24 (Trigger: GPIO_TRIGGER_FALLING)(Pull: GPIO_PULL_UP)

Constants

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PiTFT35 specific constants PITFT35_*

PITFT35_FRAMEBUFFER_DESCRIPTION = 'Adafruit PiTFT 3.5" LCD';	Description of PiTFT35 device
PITFT35_SIGNATURE = $AF000035;
PITFT35_SCREEN_WIDTH = 320;
PITFT35_SCREEN_HEIGHT = 480;

PiTFT35 GPIO constants PITFT35_LCD_*

PITFT35_LCD_DC = GPIO_PIN_25;
PITFT35_TOUCH_IRQ = GPIO_PIN_24;
PITFT35_LCD_BL = GPIO_PIN_2;	STMPE GPIO
PITFT35_LCD_BL_PWM = GPIO_PIN_18;

Type definitions

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To be documented

Public variables

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To be documented

Function declarations

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Initialization functions

procedure PiTFT35Init;

Description: Initialize the PiTFT35 unit and parameters

Note	Called only during system startup

function PiTFT35Start(Rotation:LongWord; const Device:String; DisplaySelect,TouchSelect:Word):THandle;

Description: Start the PiTFT35 driver and register the Touch, Backlight (GPIO) and Framebuffer devices associated with the display

Rotation	The rotation of the display (eg FRAMEBUFFER_ROTATION_180)
Device	The SPI device that the HX8357D and STMPE610 devices are connected to
DisplaySelect	The SPI chip select of the HX8357D LCD controller
TouchSelect	The SPI chip select of the STMPE610 touch controller
Return	The handle of the PiTFT35 on success or INVALID_HANDLE_VALUE on failure
Note	This function will be called during startup if the parameter PITFT35_AUTOSTART is True Can be called multiple times to support more than one PiTFT LCD display

function PiTFT35Stop(Handle:THandle):Boolean;

Description: Stop the PiTFT35 driver and deregister the Touch, Backlight (GPIO) and Framebuffer devices associated with the display

Handle	The handle of the PiTFT35 or INVALID_HANDLE_VALUE for the default display
Return	True if completed or False on failure

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