slint/internal/backends/mcu/pico_st7789.rs

385 lines
13 KiB
Rust

// Copyright © SixtyFPS GmbH <info@slint-ui.com>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-commercial
extern crate alloc;
use alloc::boxed::Box;
pub use cortex_m_rt::entry;
use embedded_hal::blocking::spi::Transfer;
use embedded_hal::digital::v2::{InputPin, OutputPin};
use embedded_time::rate::*;
use rp_pico::hal::pac;
use rp_pico::hal::prelude::*;
use rp_pico::hal::{self, Timer};
use defmt_rtt as _; // global logger
#[cfg(feature = "panic-probe")]
use panic_probe as _;
#[alloc_error_handler]
fn oom(layout: core::alloc::Layout) -> ! {
panic!("Out of memory {:?}", layout);
}
use alloc_cortex_m::CortexMHeap;
use crate::{Devices, PhysicalRect, PhysicalSize};
const HEAP_SIZE: usize = 200 * 1024;
static mut HEAP: [u8; HEAP_SIZE] = [0; HEAP_SIZE];
#[global_allocator]
static ALLOCATOR: CortexMHeap = CortexMHeap::empty();
// 16ns for serial clock cycle (write), page 43 of https://www.waveshare.com/w/upload/a/ae/ST7789_Datasheet.pdf
const SPI_ST7789VW_MAX_FREQ: embedded_time::rate::Hertz = embedded_time::rate::Hertz(62_500_000u32);
pub fn init() {
let mut pac = pac::Peripherals::take().unwrap();
let core = pac::CorePeripherals::take().unwrap();
let mut watchdog = hal::watchdog::Watchdog::new(pac.WATCHDOG);
let clocks = hal::clocks::init_clocks_and_plls(
rp_pico::XOSC_CRYSTAL_FREQ,
pac.XOSC,
pac.CLOCKS,
pac.PLL_SYS,
pac.PLL_USB,
&mut pac.RESETS,
&mut watchdog,
)
.ok()
.unwrap();
let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer());
unsafe { ALLOCATOR.init(&mut HEAP as *const u8 as usize, core::mem::size_of_val(&HEAP)) }
let sio = hal::sio::Sio::new(pac.SIO);
let pins = rp_pico::Pins::new(pac.IO_BANK0, pac.PADS_BANK0, sio.gpio_bank0, &mut pac.RESETS);
let _spi_sclk = pins.gpio10.into_mode::<hal::gpio::FunctionSpi>();
let _spi_mosi = pins.gpio11.into_mode::<hal::gpio::FunctionSpi>();
let _spi_miso = pins.gpio12.into_mode::<hal::gpio::FunctionSpi>();
let spi = hal::spi::Spi::<_, _, 8>::new(pac.SPI1);
let spi = spi.init(
&mut pac.RESETS,
clocks.peripheral_clock.freq(),
SPI_ST7789VW_MAX_FREQ,
&embedded_hal::spi::MODE_3,
);
// FIXME: a cleaner way to get a static reference, or be able to use non-static backend
let spi = Box::leak(Box::new(shared_bus::BusManagerSimple::new(spi)));
let rst = pins.gpio15.into_push_pull_output();
let dc = pins.gpio8.into_push_pull_output();
let cs = pins.gpio9.into_push_pull_output();
let di = display_interface_spi::SPIInterface::new(spi.acquire_spi(), dc, cs);
let mut display = st7789::ST7789::new(di, rst, 320, 240);
// Turn on backlight
{
let mut bl = pins.gpio13.into_push_pull_output();
bl.set_low().unwrap();
delay.delay_us(10_000);
bl.set_high().unwrap();
}
display.init(&mut delay).unwrap();
display.set_orientation(st7789::Orientation::Landscape).unwrap();
let touch = xpt2046::XPT2046::new(
pins.gpio17.into_pull_down_input(),
pins.gpio16.into_push_pull_output(),
spi.acquire_spi(),
)
.unwrap();
let timer = Timer::new(pac.TIMER, &mut pac.RESETS);
crate::init_with_display(PicoDevices { display, touch, last_touch: Default::default(), timer });
}
struct PicoDevices<Display, Touch> {
display: Display,
touch: Touch,
last_touch: Option<i_slint_core::graphics::Point>,
timer: Timer,
}
impl<Display: Devices, IRQ: InputPin, CS: OutputPin<Error = IRQ::Error>, SPI: Transfer<u8>> Devices
for PicoDevices<Display, xpt2046::XPT2046<IRQ, CS, SPI>>
{
fn screen_size(&self) -> PhysicalSize {
self.display.screen_size()
}
fn fill_region(&mut self, region: PhysicalRect, pixels: &[super::TargetPixel]) {
self.display.fill_region(region, pixels)
}
fn debug(&mut self, text: &str) {
self.display.debug(text)
}
fn read_touch_event(&mut self) -> Option<i_slint_core::input::MouseEvent> {
let button = i_slint_core::items::PointerEventButton::left;
self.touch
.read()
.map_err(|_| ())
.unwrap()
.map(|point| {
let size = self.display.screen_size().to_f32();
let pos = euclid::point2(point.x * size.width, point.y * size.height).cast();
match self.last_touch.replace(pos) {
Some(_) => i_slint_core::input::MouseEvent::MouseMoved { pos },
None => i_slint_core::input::MouseEvent::MousePressed { pos, button },
}
})
.or_else(|| {
self.last_touch
.take()
.map(|pos| i_slint_core::input::MouseEvent::MouseReleased { pos, button })
})
}
fn time(&self) -> core::time::Duration {
core::time::Duration::from_micros(self.timer.get_counter())
}
}
mod xpt2046 {
use embedded_hal::blocking::spi::Transfer;
use embedded_hal::digital::v2::{InputPin, OutputPin};
use embedded_time::rate::Extensions;
use euclid::default::Point2D;
pub struct XPT2046<IRQ: InputPin, CS: OutputPin, SPI: Transfer<u8>> {
irq: IRQ,
cs: CS,
spi: SPI,
pressed: bool,
}
impl<PinE, IRQ: InputPin<Error = PinE>, CS: OutputPin<Error = PinE>, SPI: Transfer<u8>>
XPT2046<IRQ, CS, SPI>
{
pub fn new(irq: IRQ, mut cs: CS, spi: SPI) -> Result<Self, PinE> {
cs.set_high()?;
Ok(Self { irq, cs, spi, pressed: false })
}
pub fn read(&mut self) -> Result<Option<Point2D<f32>>, Error<PinE, SPI::Error>> {
const PRESS_THRESHOLD: i32 = -20_000;
const RELEASE_THRESHOLD: i32 = -30_000;
let threshold = if self.pressed { RELEASE_THRESHOLD } else { PRESS_THRESHOLD };
self.pressed = false;
if self.irq.is_low().map_err(|e| Error::Pin(e))? {
const CMD_X_READ: u8 = 0b10010000;
const CMD_Y_READ: u8 = 0b11010000;
const CMD_Z1_READ: u8 = 0b10110001;
const CMD_Z2_READ: u8 = 0b11000001;
// These numbers were measured approximately.
const MIN_X: u32 = 1900;
const MAX_X: u32 = 30300;
const MIN_Y: u32 = 2300;
const MAX_Y: u32 = 30300;
// FIXME! how else set the frequency to this device
unsafe { set_spi_freq(3_000_000u32.Hz()) };
self.cs.set_low().map_err(|e| Error::Pin(e))?;
macro_rules! xchg {
($byte:expr) => {
match self
.spi
.transfer(&mut [$byte, 0, 0])
.map_err(|e| Error::Transfer(e))?
{
[_, h, l] => ((*h as u32) << 8) | (*l as u32),
_ => return Err(Error::InternalError),
}
};
}
let z1 = xchg!(CMD_Z1_READ);
let z2 = xchg!(CMD_Z2_READ);
let z = z1 as i32 - z2 as i32;
if z < threshold {
xchg!(0);
self.cs.set_high().map_err(|e| Error::Pin(e))?;
unsafe { set_spi_freq(super::SPI_ST7789VW_MAX_FREQ) };
return Ok(None);
}
xchg!(CMD_X_READ | 1); // Dummy read, first read is a outlier
let mut point = Point2D::new(0u32, 0u32);
for _ in 0..10 {
let y = xchg!(CMD_Y_READ);
let x = xchg!(CMD_X_READ);
point += euclid::vec2(i16::MAX as u32 - x, y)
}
let z1 = xchg!(CMD_Z1_READ);
let z2 = xchg!(CMD_Z2_READ);
let z = z1 as i32 - z2 as i32;
xchg!(0);
self.cs.set_high().map_err(|e| Error::Pin(e))?;
unsafe { set_spi_freq(super::SPI_ST7789VW_MAX_FREQ) };
if z < RELEASE_THRESHOLD {
return Ok(None);
}
point /= 10;
self.pressed = true;
Ok(Some(euclid::point2(
point.x.saturating_sub(MIN_X) as f32 / (MAX_X - MIN_X) as f32,
point.y.saturating_sub(MIN_Y) as f32 / (MAX_Y - MIN_Y) as f32,
)))
} else {
Ok(None)
}
}
}
pub enum Error<PinE, TransferE> {
Pin(PinE),
Transfer(TransferE),
InternalError,
}
unsafe fn set_spi_freq(freq: impl Into<super::Hertz<u32>>) {
// FIXME: the touchscreen and the LCD have different frequencies, but we cannot really set different frequencies to different SpiProxy without this hack
rp_pico::hal::spi::Spi::<_, _, 8>::new(rp_pico::hal::pac::Peripherals::steal().SPI1)
.set_baudrate(125_000_000u32.Hz(), freq);
}
}
#[cfg(not(feature = "panic-probe"))]
#[inline(never)]
#[panic_handler]
fn panic(info: &core::panic::PanicInfo) -> ! {
// Safety: it's ok to steal here since we are in the panic handler, and the rest of the code will not be run anymore
let (mut pac, core) = unsafe { (pac::Peripherals::steal(), pac::CorePeripherals::steal()) };
let sio = hal::sio::Sio::new(pac.SIO);
let pins = rp_pico::Pins::new(pac.IO_BANK0, pac.PADS_BANK0, sio.gpio_bank0, &mut pac.RESETS);
let mut led = pins.led.into_push_pull_output();
led.set_high().unwrap();
// Re-init the display
let mut watchdog = hal::watchdog::Watchdog::new(pac.WATCHDOG);
let clocks = hal::clocks::init_clocks_and_plls(
rp_pico::XOSC_CRYSTAL_FREQ,
pac.XOSC,
pac.CLOCKS,
pac.PLL_SYS,
pac.PLL_USB,
&mut pac.RESETS,
&mut watchdog,
)
.ok()
.unwrap();
let _spi_sclk = pins.gpio10.into_mode::<hal::gpio::FunctionSpi>();
let _spi_mosi = pins.gpio11.into_mode::<hal::gpio::FunctionSpi>();
let _spi_miso = pins.gpio12.into_mode::<hal::gpio::FunctionSpi>();
let spi = hal::spi::Spi::<_, _, 8>::new(pac.SPI1);
let spi = spi.init(
&mut pac.RESETS,
clocks.peripheral_clock.freq(),
4_000_000u32.Hz(),
&embedded_hal::spi::MODE_3,
);
let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer());
let rst = pins.gpio15.into_push_pull_output();
let dc = pins.gpio8.into_push_pull_output();
let cs = pins.gpio9.into_push_pull_output();
let di = display_interface_spi::SPIInterface::new(spi, dc, cs);
let mut display = st7789::ST7789::new(di, rst, 320, 240);
// Turn on backlight
{
let mut bl = pins.gpio13.into_push_pull_output();
bl.set_low().unwrap();
delay.delay_us(10_000);
bl.set_high().unwrap();
}
use core::fmt::Write;
use embedded_graphics::{
draw_target::DrawTarget,
mono_font::{ascii::FONT_6X10, MonoTextStyle},
pixelcolor::Rgb565,
prelude::*,
text::Text,
};
display.init(&mut delay).unwrap();
display.set_orientation(st7789::Orientation::Landscape).unwrap();
display.fill_solid(&display.bounding_box(), Rgb565::new(0x00, 0x25, 0xff)).unwrap();
struct WriteToScreen<'a, D> {
x: i32,
y: i32,
width: i32,
style: MonoTextStyle<'a, Rgb565>,
display: &'a mut D,
}
let mut writer = WriteToScreen {
x: 0,
y: 1,
width: display.bounding_box().size.width as i32 / 6 - 1,
style: MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE),
display: &mut display,
};
impl<'a, D: DrawTarget<Color = Rgb565>> Write for WriteToScreen<'a, D> {
fn write_str(&mut self, mut s: &str) -> Result<(), core::fmt::Error> {
while !s.is_empty() {
let (x, y) = (self.x, self.y);
let end_of_line = s
.find(|c| {
if c == '\n' || self.x > self.width {
self.x = 0;
self.y += 1;
true
} else {
self.x += 1;
false
}
})
.unwrap_or(s.len());
let (line, rest) = s.split_at(end_of_line);
let sz = self.style.font.character_size;
Text::new(line, Point::new(x * sz.width as i32, y * sz.height as i32), self.style)
.draw(self.display)
.map_err(|_| core::fmt::Error)?;
s = rest.strip_prefix('\n').unwrap_or(rest);
}
Ok(())
}
}
write!(writer, "{}", info).unwrap();
loop {
delay.delay_ms(100);
led.set_low().unwrap();
delay.delay_ms(100);
led.set_high().unwrap();
}
}