Files
creaturedex/src/drivers/tertiary_lcd.rs
T
2026-08-29 18:17:25 +02:00

411 lines
12 KiB
Rust

use embedded_hal_bus::i2c::AtomicDevice;
use esp_hal::delay::Delay;
use i2c_character_display::{CharacterDisplayPCF8574T, LcdDisplayType};
use log::error;
use crate::create_custom_char_set;
use crate::drivers::i2c_bus::{I2cBus, I2cDevice};
type GenericTertiaryDisplay<I2C> = CharacterDisplayPCF8574T<I2C, Delay>;
type TertiaryDisplayRaw<'a> = GenericTertiaryDisplay<I2cDevice<'a>>;
pub type TertiaryDisplayError<'a> = i2c_character_display::CharacterDisplayError<I2cDevice<'a>>;
pub struct TertiaryDisplayPinConfiguration<'a> {
pub i2c: I2cBus<'a>,
}
impl<'a> TertiaryDisplayPinConfiguration<'a> {
pub fn build(self) -> Result<TertiaryDisplay<'a>, Self> {
let device = AtomicDevice::new(self.i2c);
let mut lcd = CharacterDisplayPCF8574T::new(device, LcdDisplayType::Lcd16x2, Delay::new());
match lcd.init() {
Ok(()) => {
log::info!("I2C tertiary LCD initialized on PCF8574T at address 0x27");
Ok(TertiaryDisplay {
display: lcd,
charset: create_custom_char_set!(),
})
}
Err(e) => {
log::error!("I2C tertiary LCD init failed on PCF8574T at address 0x27: {e}");
Err(self)
}
}
}
}
#[derive(Debug, Clone)]
pub enum TertiaryDisplayWriteError<'a> {
Display(TertiaryDisplayError<'a>),
Format(LinesError),
}
impl<'a> From<TertiaryDisplayError<'a>> for TertiaryDisplayWriteError<'a> {
fn from(value: TertiaryDisplayError<'a>) -> Self {
Self::Display(value)
}
}
impl From<LinesError> for TertiaryDisplayWriteError<'_> {
fn from(value: LinesError) -> Self {
Self::Format(value)
}
}
impl<'a> core::fmt::Display for TertiaryDisplayWriteError<'a> {
fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
match self {
Self::Display(e) => write!(f, "display error: {e}"),
Self::Format(e) => write!(f, "format error: {e}"),
}
}
}
pub struct TertiaryDisplay<'a> {
display: TertiaryDisplayRaw<'a>,
charset: CustomCharset,
}
impl<'a> TertiaryDisplay<'a> {
pub const WIDTH: usize = 16;
pub const ROWS: usize = 2;
pub fn inner_mut(&mut self) -> &mut TertiaryDisplayRaw<'a> {
&mut self.display
}
pub fn load_charset(&mut self, charset: CustomCharset) -> Result<(), TertiaryDisplayError<'a>> {
self.charset = charset;
for (index, charmap) in self
.charset
.set
.into_iter()
.enumerate()
.take(self.charset.len)
{
self.display
.create_char(index as u8, charmap)
.inspect_err(|e| error!("I2C Custom character {index} init failed: {e}"))?;
}
Ok(())
}
pub fn clear(&mut self) -> Result<(), TertiaryDisplayError<'a>> {
if let Err(e) = self.display.clear() {
error!("I2C LCD clear failed; bus may be busy or device unresponsive");
return Err(e);
}
Ok(())
}
/// Writes text to the LCD. Normal strings wrap by default but this can be controlled
/// via explicit [`Lines::checked`].
pub fn write<'b, L: Into<Lines<'b>>>(
&mut self,
text: L,
) -> Result<(), TertiaryDisplayWriteError<'a>> {
let lines = text.into();
// Use original to get correct position in original string
lines
.original
.iter()
.try_for_each(|text| Lines::invalid_chars(text, Some(&self.charset)))?;
let lines = lines.into_result()?;
self.display
.clear()
.inspect_err(|e| error!("I2C LCD clear failed before wrapped write: {e}"))?;
for (row, line) in lines.into_iter().enumerate() {
self.display.set_cursor(0, row as u8).inspect_err(|e| {
error!("I2C LCD cursor move failed while writing wrapped row {row}: {e}")
})?;
self.display
.print(line)
.inspect_err(|e| error!("I2C LCD wrapped write failed on row {row}: {e}"))?;
}
Ok(())
}
}
#[derive(Debug, PartialEq, Eq, Clone)]
pub enum LinesError {
ColumnOverflow { line: u8, columns: usize },
LineOverflow,
InvalidChar { position: usize, symbol: char },
}
impl core::fmt::Display for LinesError {
fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
match self {
Self::ColumnOverflow { line, columns } => {
write!(
f,
"text too long for line {line}: {columns} > {}",
TertiaryDisplay::WIDTH
)
}
Self::LineOverflow => write!(f, "text has too many lines"),
Self::InvalidChar { position, symbol } => {
write!(f, "Invalid character {symbol} at offset {position}")
}
}
}
}
#[derive(Debug, PartialEq, Eq, Clone)]
pub struct Lines<'a> {
pub lines: Result<[&'a str; TertiaryDisplay::ROWS], LinesError>,
/// Unmodified original string. Only first entry is populated unless constructed with [`by_line`]
pub original: [&'a str; TertiaryDisplay::ROWS],
}
impl<'a> Lines<'a> {
pub fn into_result(self) -> Result<[&'a str; TertiaryDisplay::ROWS], LinesError> {
self.lines
}
/// Validates that the text contains only non-control ASCII characters,
/// newlines, and contiguous custom characters up to `charset.len`.
/// If `charset` is `None`, allow any custom char up to and including maximum.
pub fn invalid_chars(text: &str, charset: Option<&CustomCharset>) -> Result<(), LinesError> {
for (pos, c) in text.char_indices() {
let is_standard_valid = c == '\n' || (' '..='~').contains(&c);
if is_standard_valid {
continue;
}
let first_invalid_custom_char =
charset.map(|c| c.len).unwrap_or(CUSTOM_CHAR_COUNT.into());
if (c as usize) >= first_invalid_custom_char {
return Err(LinesError::InvalidChar {
position: pos,
symbol: c,
});
}
}
Ok(())
}
/// Checks pre-split lines strictly for length and valid characters.
pub fn by_line(lines: [&'a str; TertiaryDisplay::ROWS]) -> Self {
let this = |res| Self {
lines: res,
original: lines,
};
for line in lines.iter() {
if let Err(e) = Self::invalid_chars(line, None) {
return this(Err(e));
}
}
for (i, line) in lines.iter().enumerate() {
if line.len() > TertiaryDisplay::WIDTH {
return this(Err(LinesError::ColumnOverflow {
line: i as u8,
columns: line.len(),
}));
}
}
this(Ok(lines))
}
/// Strictly checks an input string.
/// Fails if there are invalid chars, too many newlines, or if any segment exceeds WIDTH.
pub fn checked(input: &'a str) -> Self {
let this = |res| Self {
lines: res,
original: [input, ""],
};
if let Err(e) = Self::invalid_chars(input, None) {
return this(Err(e));
}
let mut out = [""; TertiaryDisplay::ROWS];
let mut parts = input.split('\n');
for (i, out) in out.iter_mut().enumerate() {
if let Some(part) = parts.next() {
if part.len() > TertiaryDisplay::WIDTH {
return this(Err(LinesError::ColumnOverflow {
line: i as u8,
columns: part.len(),
}));
}
*out = part;
}
}
if parts.next().is_some() {
return this(Err(LinesError::LineOverflow));
}
this(Ok(out))
}
/// Wraps text automatically at `WIDTH` or at newlines.
/// Discards (clamps) any leftover text that exceeds `ROWS`.
/// Fails immediately if invalid characters are present.
pub fn clamped(input: &'a str) -> Self {
let this = |res| Self {
lines: res,
original: [input, ""],
};
if let Err(e) = Self::invalid_chars(input, None) {
return this(Err(e));
}
let mut out = [""; TertiaryDisplay::ROWS];
let mut remaining = input;
for out in out.iter_mut() {
if remaining.is_empty() {
break;
}
let (segment, rest) = Self::next_segment(remaining, TertiaryDisplay::WIDTH);
*out = segment;
remaining = rest;
}
this(Ok(out))
}
/// Helper function to slice an ASCII string up to `max_width`
/// or until the next newline, whichever comes first.
fn next_segment(s: &str, max_width: usize) -> (&str, &str) {
let nl_pos = s.find('\n');
let split_pos = match nl_pos {
Some(pos) if pos <= max_width => pos,
_ => core::cmp::min(s.len(), max_width),
};
let segment = &s[..split_pos];
let mut rest = &s[split_pos..];
if let Some(stripped) = rest.strip_prefix('\n') {
rest = stripped;
}
(segment, rest)
}
}
impl<'a> From<&'a str> for Lines<'a> {
fn from(value: &'a str) -> Self {
Self::clamped(value)
}
}
impl<'a> From<&'a alloc::string::String> for Lines<'a> {
fn from(value: &'a alloc::string::String) -> Self {
Self::clamped(value)
}
}
/// 5x8 pixel charmap. Each set bit is a black pixel.
pub type CharMap = [u8; 8];
pub struct CustomCharset {
set: [CharMap; CUSTOM_CHAR_COUNT as usize],
len: usize,
}
impl core::ops::Index<CharMap> for CustomCharset {
type Output = &'static str;
fn index(&self, map: CharMap) -> &Self::Output {
let encoded = self.set[..self.len]
.iter()
.position(|&m| m == map)
.expect("Unknown char map in this set.");
match encoded {
0 => &"\x00",
1 => &"\x01",
2 => &"\x02",
3 => &"\x03",
4 => &"\x04",
5 => &"\x05",
6 => &"\x06",
7 => &"\x07",
8 => &"\x08",
9 => &"\x09",
10 => &"\x0A",
11 => &"\x0B",
12 => &"\x0C",
13 => &"\x0D",
14 => &"\x0E",
15 => &"\x0F",
pos => unreachable!(
"More than {CUSTOM_CHAR_COUNT} (=max) elements in array? Found element at {pos}."
),
}
}
}
#[macro_export]
macro_rules! create_custom_char_set {
() => {{
CustomCharset { set: [EMPTY; CUSTOM_CHAR_COUNT as usize], len: 0 }
}};
($($char:expr),+ $(,)?) => {{
// Count how many characters were passed using macro repetition length
const LEN: usize = [$(stringify!($char)),+].len();
// Ensure we don't exceed the defined maximum capacity
const _: () = assert!(
LEN <= CUSTOM_CHAR_COUNT as usize,
"Too many characters provided for CUSTOM_CHAR_COUNT"
);
// Build a fixed-size array populated with the provided characters,
// and pad the rest with empty CharMaps (zeros) to fit CUSTOM_CHAR_COUNT.
const SET: [CharMap; CUSTOM_CHAR_COUNT as usize] = {
let mut buffer = [[0u8; 8]; CUSTOM_CHAR_COUNT as usize];
let input = [$($char),*];
let mut i = 0;
while i < input.len() {
buffer[i] = input[i];
i += 1;
}
buffer
};
CustomCharset {
set: SET,
len: LEN,
}
}};
}
pub const CUSTOM_CHAR_COUNT: u8 = 16;
pub const HEART: CharMap = [
0b00000, // Top row
0b01010, // * *
0b11111, // *****
0b11111, // *****
0b01110, // ***
0b00100, // *
0b00000, // Bottom row
0b00000, // Cursor line (usually left blank)
];
pub const EMPTY: CharMap = [0; 8];
pub const BOX: CharMap = [
0b11111, 0b11111, 0b11111, 0b11111, 0b11111, 0b11111, 0b11111,
0b00000, // Cursor line (usually left blank)
];
pub const EXAMPLE: CustomCharset = create_custom_char_set!(HEART, BOX, EMPTY);