hdw-tft.c File Reference

Macros
#define	SWAP(x)   ((x >> 8) | (x << 8))
	Swap the upper and lower bytes in a 16-bit word.
#define	PARALLEL_LINES   16
	The number of parallel lines used in a SPI transfer.
#define	LCD_BK_LIGHT_ON_LEVEL   1
	The GPIO level to turn the backlight on.
#define	LCD_BK_LIGHT_OFF_LEVEL   0
	The GPIO level to turn the backlight off.
#define	LCD_CMD_BITS   8
	The number of bits in an LCD control command.
#define	LCD_PARAM_BITS   8
	The number of bits for an LCD control command's parameter.
#define	NUM_S_LINES   2

Functions
esp_err_t	setTFTBacklightBrightness (uint8_t intensity)
	Set TFT Backlight brightness. setTftBrightnessSetting() should be called instead if the new volume should be persistent through a reboot.
void	initTFT (spi_host_device_t spiHost, gpio_num_t sclk, gpio_num_t mosi, gpio_num_t dc, gpio_num_t cs, gpio_num_t rst, gpio_num_t backlight, bool isPwmBacklight, ledc_channel_t ledcChannel, ledc_timer_t ledcTimer, uint8_t brightness)
	Initialize a TFT display and return it through a pointer arg.
void	deinitTFT (void)
	Deinitialize the TFT display.
paletteColor_t *	getPxTftFramebuffer (void)
	Return the pixel framebuffer, which is (TFT_WIDTH * TFT_HEIGHT) pixels in row order, starting from the top left. This can be used t directly modify individual pixels without calling setPxTft()
void	disableTFTBacklight (void)
	Disable the backlight (for power down)
void	enableTFTBacklight (void)
	Enable the backlight.
void	setPxTft (int16_t x, int16_t y, paletteColor_t px)
	Set a single pixel in the display, with bounds check.
paletteColor_t	getPxTft (int16_t x, int16_t y)
	Get a single pixel in the display.
void	clearPxTft (void)
	Clear all pixels in the display to black.
void	drawDisplayTft (fnBackgroundDrawCallback_t fnBackgroundDrawCallback)
	Send the current framebuffer to the TFT display over the SPI bus.

Variables
paletteColor_t *	pFrameBuffer = NULL

Macro Definition Documentation

SWAP

#define SWAP

(

x

)

((x >> 8) | (x << 8))

Swap the upper and lower bytes in a 16-bit word.

PARALLEL_LINES

#define PARALLEL_LINES   16

The number of parallel lines used in a SPI transfer.

To speed up transfers, every SPI transfer sends a bunch of lines. This define specifies how many. More means more memory use, but less overhead for setting up and finishing transfers. Make sure TFT_HEIGHT is dividable by this.

LCD_BK_LIGHT_ON_LEVEL

#define LCD_BK_LIGHT_ON_LEVEL   1

The GPIO level to turn the backlight on.

LCD_BK_LIGHT_OFF_LEVEL

#define LCD_BK_LIGHT_OFF_LEVEL   0

The GPIO level to turn the backlight off.

LCD_CMD_BITS

#define LCD_CMD_BITS   8

The number of bits in an LCD control command.

LCD_PARAM_BITS

#define LCD_PARAM_BITS   8

The number of bits for an LCD control command's parameter.

NUM_S_LINES

#define NUM_S_LINES   2

Function Documentation

setTFTBacklightBrightness()

esp_err_t setTFTBacklightBrightness

(

uint8_t

intensity

)

Set TFT Backlight brightness. setTftBrightnessSetting() should be called instead if the new volume should be persistent through a reboot.

Parameters

intensity

The brightness, 0 to MAX_TFT_BRIGHTNESS

Returns

value is 0 if OK nonzero if error.

initTFT()

void initTFT	(	spi_host_device_t	spiHost,
		gpio_num_t	sclk,
		gpio_num_t	mosi,
		gpio_num_t	dc,
		gpio_num_t	cs,
		gpio_num_t	rst,
		gpio_num_t	backlight,
		bool	isPwmBacklight,
		ledc_channel_t	ledcChannel,
		ledc_timer_t	ledcTimer,
		uint8_t	brightness )

Initialize a TFT display and return it through a pointer arg.

Parameters

spiHost	The SPI host to use for this display
sclk	The GPIO for the SCLK pin
mosi	The GPIO for the MOSI pin
dc	The GPIO for the TFT SPI data or command selector pin
cs	The GPIO for the chip select pin
rst	The GPIO for the RESET pin
backlight	The GPIO used to PWM control the backlight
isPwmBacklight	true to set up the backlight as PWM, false to have it be on/off
ledcChannel	The LEDC channel to use for the PWM backlight
ledcTimer	The LEDC timer to use for the PWM backlight
brightness	The initial backlight brightness

deinitTFT()

void deinitTFT

(

void

)

Deinitialize the TFT display.

getPxTftFramebuffer()

paletteColor_t * getPxTftFramebuffer

(

void

)

Return the pixel framebuffer, which is (TFT_WIDTH * TFT_HEIGHT) pixels in row order, starting from the top left. This can be used t directly modify individual pixels without calling setPxTft()

Returns

The pixel framebuffer

disableTFTBacklight()

void disableTFTBacklight

(

void

)

Disable the backlight (for power down)

enableTFTBacklight()

void enableTFTBacklight

(

void

)

Enable the backlight.

setPxTft()

void setPxTft	(	int16_t	x,
		int16_t	y,
		paletteColor_t	px )

Set a single pixel in the display, with bounds check.

Parameters

x	The x coordinate of the pixel to set
y	The y coordinate of the pixel to set
px	The color of the pixel to set

getPxTft()

paletteColor_t getPxTft	(	int16_t	x,
		int16_t	y )

Get a single pixel in the display.

Parameters

x	The x coordinate of the pixel to get
y	The y coordinate of the pixel to get

Returns

paletteColor_t The color of the given pixel, or black if out of bounds

clearPxTft()

void clearPxTft

(

void

)

Clear all pixels in the display to black.

drawDisplayTft()

void drawDisplayTft

(

fnBackgroundDrawCallback_t

fnBackgroundDrawCallback

)

Send the current framebuffer to the TFT display over the SPI bus.

This function can be called as quickly as possible

Because the SPI driver handles transactions in the background, we can calculate the next line while the previous one is being sent.

Parameters

fnBackgroundDrawCallback

A function pointer to draw backgrounds while the transmission is occurring

Variable Documentation

pFrameBuffer

paletteColor_t* pFrameBuffer = NULL