Unit PiTFT35
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Description
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 STMPE610 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 STMPE610 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
PITFT35_* PITFT35_FRAMEBUFFER_DESCRIPTION = 'Adafruit PiTFT 3.5" LCD';
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Description of PiTFT35 device |
PITFT35_SIGNATURE = $AF000035;
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PITFT35_SCREEN_WIDTH = 320;
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PITFT35_SCREEN_HEIGHT = 480;
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PITFT35_LCD_* PITFT35_LCD_DC = GPIO_PIN_25;
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PITFT35_TOUCH_IRQ = GPIO_PIN_24;
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PITFT35_LCD_BL = GPIO_PIN_2;
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STMPE GPIO |
PITFT35_LCD_BL_PWM = GPIO_PIN_18;
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Type definitions
PiTFT35 specific types
PPiTFT35LCD = ^TPiTFT35LCD;
TPiTFT35LCD = record
Signature:LongWord;
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Signature for entry validation |
Rotation:LongWord;
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Framebuffer rotation (eg FRAMEBUFFER_ROTATION_180) |
SPI:PSPIDevice;
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SPI device for this display |
GPIO:PGPIODevice;
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GPIO device for this display |
Touch:PTouchDevice;
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Touch (STMPE) device for this display |
Backlight:PGPIODevice;
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Backlight GPIO (STMPE) device for this display |
Framebuffer:PFramebufferDevice;
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Framebuffer (HX8357D) device for this display |
Public variables
PiTFT35 specific variables
PITFT35_SPI_DEVICE:String = 'SPI0';
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PITFT35_LCD_CHIPSELECT:Word = SPI_CS_0;
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PITFT35_TOUCH_CHIPSELECT:Word = SPI_CS_1;
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PITFT35_BL_PWM_ENABLE:LongBool = True;
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Function declarations
Initialization functions
procedure PiTFT35Init;
| Note | Called only during system startup |
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function PiTFT35Start(Rotation:LongWord; const Device:String; DisplaySelect,TouchSelect:Word):THandle;
| Rotation | The rotation of the display (eg FRAMEBUFFER_ROTATION_180) |
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| 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;
| Handle | The handle of the PiTFT35 or INVALID_HANDLE_VALUE for the default display |
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| Return | True if completed or False on failure |
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