Merge branch 'main' into nes

fix

user_apps/calculator/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "calculator"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+embedded-graphics = "0.8.1"
+embedded-layout = "0.4.2"

user_apps/calculator/build.rs

@@ -0,0 +1,28 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}

user_apps/calculator/src/main.rs

@@ -0,0 +1,200 @@
+#![no_std]
+#![no_main]
+
+extern crate alloc;
+use alloc::{format, string::String, vec, vec::Vec};
+use core::panic::PanicInfo;
+use embedded_graphics::{
+    Drawable,
+    geometry::{Dimensions, Point},
+    mono_font::{MonoTextStyle, ascii::FONT_7X14, iso_8859_1::FONT_10X20},
+    pixelcolor::Rgb565,
+    prelude::{Primitive, RgbColor},
+    primitives::{PrimitiveStyle, Rectangle},
+    text::Text,
+};
+use embedded_layout::{
+    View,
+    align::{Align, horizontal, vertical},
+    layout::linear::LinearLayout,
+    prelude::Chain,
+};
+use userlib::{
+    display::Display,
+    get_key,
+    keyboard::{KeyCode, KeyState},
+    println,
+};
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location(),);
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+pub fn main() {
+    println!("Starting Calculator app");
+    let mut display = Display::take().unwrap();
+
+    let mut input = vec!['e', 'x', 'p', 'r', ':', ' '];
+    let input_min = input.len();
+    let mut dirty = true;
+    let mut last_area: Option<(Rectangle, Rectangle)> = None;
+
+    LinearLayout::vertical(Chain::new(Text::new(
+        "Calculator!",
+        Point::zero(),
+        MonoTextStyle::new(&FONT_10X20, Rgb565::WHITE),
+    )))
+    .arrange()
+    .align_to(&display.bounding_box(), horizontal::Center, vertical::Top)
+    .draw(&mut display)
+    .expect("Failed to draw title");
+
+    loop {
+        if dirty {
+            let style = PrimitiveStyle::with_fill(Rgb565::BLACK);
+            if let Some(area) = last_area {
+                Rectangle::new(area.0.top_left, area.0.size)
+                    .into_styled(style)
+                    .draw(&mut display)
+                    .unwrap();
+
+                Rectangle::new(area.1.top_left, area.1.size)
+                    .into_styled(style)
+                    .draw(&mut display)
+                    .unwrap();
+            }
+
+            let text = input.iter().cloned().collect::<String>();
+
+            let style = MonoTextStyle::new(&FONT_7X14, Rgb565::WHITE);
+            let expr_layout = LinearLayout::vertical(Chain::new(Text::new(
+                &text,
+                display.bounding_box().center(),
+                style,
+            )))
+            .arrange()
+            .align_to(&display.bounding_box(), horizontal::Left, vertical::Center);
+
+            let result = if let Ok(result) = evaluate(&input[input_min..]) {
+                &format!(" = {result}")
+            } else {
+                " = Error"
+            };
+
+            let eq_layout = LinearLayout::vertical(Chain::new(Text::new(
+                result,
+                display.bounding_box().center(),
+                style,
+            )))
+            .arrange()
+            .align_to(&display.bounding_box(), horizontal::Right, vertical::Center);
+
+            last_area = Some((expr_layout.bounds(), eq_layout.bounds()));
+            expr_layout.draw(&mut display).unwrap();
+            eq_layout.draw(&mut display).unwrap();
+
+            dirty = false;
+        }
+
+        let event = get_key();
+        if event.state == KeyState::Released {
+            match event.key {
+                KeyCode::Char(ch) => {
+                    input.push(ch);
+                }
+                KeyCode::Del => {
+                    input.truncate(input_min);
+                }
+                KeyCode::Backspace => {
+                    if input.len() > input_min {
+                        input.pop();
+                    }
+                }
+                KeyCode::Esc => return,
+                _ => (),
+            }
+            dirty = true;
+        }
+    }
+}
+
+fn get_int(int: &[char]) -> Result<i32, ()> {
+    let mut output: i32 = 0;
+    for &c in int {
+        let digit = c.to_digit(10).ok_or(())? as i32;
+        output = output
+            .checked_mul(10)
+            .and_then(|v| v.checked_add(digit))
+            .ok_or(())?;
+    }
+    Ok(output)
+}
+
+fn primary(input: &[char], pos: &mut usize) -> Result<i32, ()> {
+    let mut digits = Vec::new();
+    while *pos < input.len() && input[*pos].is_ascii_digit() {
+        digits.push(input[*pos]);
+        *pos += 1;
+    }
+    if digits.is_empty() {
+        return Err(());
+    }
+    get_int(&digits)
+}
+
+fn mul_div(input: &[char], pos: &mut usize) -> Result<i32, ()> {
+    let mut value = primary(input, pos)?;
+    while *pos < input.len() {
+        let op = input[*pos];
+        if op != '*' && op != '/' {
+            break;
+        }
+        *pos += 1;
+        let rhs = primary(input, pos)?;
+        value = match op {
+            '*' => value.checked_mul(rhs).ok_or(())?,
+            '/' => {
+                if rhs == 0 {
+                    return Err(());
+                }
+                value.checked_div(rhs).ok_or(())?
+            }
+            _ => unreachable!(),
+        };
+    }
+    Ok(value)
+}
+
+fn add_sub(input: &[char], pos: &mut usize) -> Result<i32, ()> {
+    let mut value = mul_div(input, pos)?;
+    while *pos < input.len() {
+        let op = input[*pos];
+        if op != '+' && op != '-' {
+            break;
+        }
+        *pos += 1;
+        let rhs = mul_div(input, pos)?;
+        value = match op {
+            '+' => value.checked_add(rhs).ok_or(())?,
+            '-' => value.checked_sub(rhs).ok_or(())?,
+            _ => unreachable!(),
+        };
+    }
+    Ok(value)
+}
+
+fn evaluate(input: &[char]) -> Result<i32, ()> {
+    let mut pos = 0;
+    let result = add_sub(input, &mut pos)?;
+    if pos != input.len() {
+        return Err(());
+    }
+    Ok(result)
+}

user_apps/gallery/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "gallery"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+embedded-graphics = "0.8.1"
+tinybmp = "0.6.0"

user_apps/gallery/build.rs

@@ -0,0 +1,28 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}

user_apps/gallery/src/main.rs

@@ -0,0 +1,92 @@
+#![no_std]
+#![no_main]
+#![allow(static_mut_refs)]
+
+extern crate alloc;
+use alloc::{format, vec};
+use core::panic::PanicInfo;
+use embedded_graphics::{
+    Drawable, image::Image, mono_font::MonoTextStyle, mono_font::ascii::FONT_6X10,
+    pixelcolor::Rgb565, prelude::*, text::Text,
+};
+use tinybmp::Bmp;
+use userlib::{
+    display::{Display, SCREEN_HEIGHT, SCREEN_WIDTH},
+    fs::{Entries, list_dir, read_file},
+    get_key,
+    keyboard::{KeyCode, KeyState},
+    println,
+};
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location());
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+pub fn main() {
+    println!("Starting Gallery app");
+    let mut bmp_buf = vec![0_u8; 100_000];
+    let mut display = Display::take().unwrap();
+
+    let grid_cols = 3;
+    let grid_rows = 3;
+    let cell_width = SCREEN_WIDTH as i32 / grid_cols;
+    let cell_height = SCREEN_HEIGHT as i32 / grid_rows;
+
+    let mut images_drawn = 0;
+
+    let mut entries = Entries::new();
+    let files_num = list_dir("/images", &mut entries);
+
+    for file in &entries.entries()[2..files_num] {
+        if images_drawn >= grid_cols * grid_rows {
+            break; // only draw 3x3
+        }
+
+        println!("file: {}", file);
+        if file.extension().unwrap_or("") == "bmp" || file.extension().unwrap_or("") == "BMP" {
+            let file_path = format!("/images/{file}");
+
+            let read = read_file(&file_path, 0, &mut bmp_buf[..]);
+            if read > 0 {
+                let bmp = Bmp::from_slice(&bmp_buf).expect("failed to parse bmp");
+
+                let row = images_drawn / grid_cols;
+                let col = images_drawn % grid_cols;
+                let cell_x = col * cell_width;
+                let cell_y = row * cell_height;
+
+                // Center image inside cell
+                let bmp_w = bmp.size().width as i32;
+                let bmp_h = bmp.size().height as i32;
+                let x = cell_x + (cell_width - bmp_w) / 2;
+                let y = cell_y + 5; // 5px top margin
+
+                Image::new(&bmp, Point::new(x, y))
+                    .draw(&mut display)
+                    .unwrap();
+
+                let text_style = MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE);
+                let text_y = y + bmp_h + 2; // 2px gap under image
+                Text::new(file.base(), Point::new(cell_x + 2, text_y), text_style)
+                    .draw(&mut display)
+                    .unwrap();
+
+                images_drawn += 1;
+            }
+        }
+    }
+
+    loop {
+        let event = get_key();
+        if event.state != KeyState::Idle && event.key == KeyCode::Esc {
+            return;
+        }
+    }
+}

user_apps/gboy/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "gboy"
+version = "0.1.0"
+edition = "2024"
+
+[build-dependencies]
+bindgen = "0.71.0"
+cc = "1.2.44"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+selection_ui = { path = "../../selection_ui" }
+embedded-graphics = "0.8.1"

user_apps/gboy/build.rs

@@ -0,0 +1,64 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    bindgen();
+
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}
+
+fn bindgen() {
+    let bindings = bindgen::Builder::default()
+        .header("Peanut-GB/peanut_gb.h")
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
+        .disable_nested_struct_naming()
+        .clang_arg("-I../../picolibc/newlib/libc/include/")
+        .clang_arg("-I../../picolibc/build/")
+        .use_core()
+        .generate()
+        .expect("Unable to generate bindings");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("Couldn't write bindings!");
+
+    cc::Build::new()
+        .define("PEANUT_GB_IS_LITTLE_ENDIAN", None)
+        .define("ENABLE_LCD", None)
+        .file("peanut_gb_stub.c")
+        .include("Peanut-GB")
+        // optimization flags
+        .flag("-Ofast")
+        .flag("-fdata-sections")
+        .flag("-ffunction-sections")
+        .flag("-mcpu=cortex-m33")
+        .flag("-mthumb")
+        .flag("-g0")
+        .compile("peanut_gb");
+
+    println!("cargo:rustc-link-search=Peanut-GB");
+    println!("cargo:rustc-link-lib=peanut_gb");
+}

user_apps/gboy/peanut_gb_stub.c

@@ -0,0 +1 @@
+#include <peanut_gb.h>

user_apps/gboy/src/main.rs

@@ -0,0 +1,206 @@
+#![no_std]
+#![no_main]
+#![allow(static_mut_refs)]
+
+extern crate alloc;
+use alloc::{vec, vec::Vec};
+use core::{cell::LazyCell, mem::MaybeUninit, panic::PanicInfo};
+use embedded_graphics::{
+    mono_font::{MonoTextStyle, ascii::FONT_6X10},
+    pixelcolor::Rgb565,
+    prelude::RgbColor,
+};
+use selection_ui::{SelectionUi, SelectionUiError, draw_text_center};
+use userlib::{
+    display::Display,
+    format,
+    fs::{Entries, file_len, list_dir, read_file, write_file},
+    get_key,
+    keyboard::{KeyCode, KeyState},
+    println,
+};
+
+mod peanut;
+use peanut::gb_run_frame;
+
+use crate::peanut::{
+    JOYPAD_A, JOYPAD_B, JOYPAD_DOWN, JOYPAD_LEFT, JOYPAD_RIGHT, JOYPAD_SELECT, JOYPAD_START,
+    JOYPAD_UP, gb_cart_ram_read, gb_cart_ram_write, gb_error, gb_get_rom_name, gb_get_save_size,
+    gb_init, gb_init_lcd, gb_reset, gb_rom_read, gb_s, lcd_draw_line,
+};
+
+static mut DISPLAY: LazyCell<Display> = LazyCell::new(|| Display::take().unwrap());
+
+const RAM_SIZE: usize = 32 * 1024; // largest ram size is 32k
+static mut RAM: [u8; RAM_SIZE] = [0; RAM_SIZE];
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location(),);
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+const GAME_PATH: &'static str = "/games/gameboy";
+
+static mut GAME_ROM: Option<Vec<u8>> = None;
+
+pub fn main() {
+    println!("Starting Gameboy app");
+
+    let mut entries = Entries::new();
+    list_dir(GAME_PATH, &mut entries);
+
+    let mut files = entries.entries();
+    files.retain(|e| {
+        let ext = e.extension().unwrap_or("");
+        ext == "gb" || ext == "GB"
+    });
+    let mut roms = files.iter().map(|e| e.full_name()).collect::<Vec<&str>>();
+    roms.sort();
+
+    let selection = {
+        let display = unsafe { &mut *DISPLAY };
+        let mut selection_ui = SelectionUi::new(&roms);
+        match selection_ui.run_selection_ui(display) {
+            Ok(maybe_sel) => maybe_sel,
+            Err(e) => match e {
+                SelectionUiError::SelectionListEmpty => {
+                    draw_text_center(
+                        display,
+                        &format!("No Roms were found in {}", GAME_PATH),
+                        MonoTextStyle::new(&FONT_6X10, Rgb565::RED),
+                    )
+                    .expect("Display Error");
+                    None
+                }
+                SelectionUiError::DisplayError(_) => panic!("Display Error"),
+            },
+        }
+    };
+
+    assert!(selection.is_some());
+
+    let file_name = format!("{}/{}", GAME_PATH, roms[selection.unwrap()]);
+    let size = file_len(&file_name);
+    unsafe { GAME_ROM = Some(vec![0_u8; size]) };
+    let read = read_file(&file_name, 0, unsafe { GAME_ROM.as_mut().unwrap() });
+    assert!(size == read);
+    println!("Rom size: {}", read);
+
+    let mut gb = MaybeUninit::<gb_s>::uninit();
+
+    let init_status = unsafe {
+        gb_init(
+            gb.as_mut_ptr(),
+            Some(gb_rom_read),
+            Some(gb_cart_ram_read),
+            Some(gb_cart_ram_write),
+            Some(gb_error),
+            core::ptr::null_mut(),
+        )
+    };
+    println!("gb init status: {}", init_status);
+
+    unsafe {
+        load_save(&mut gb.assume_init());
+    }
+
+    unsafe {
+        gb_init_lcd(gb.as_mut_ptr(), Some(lcd_draw_line));
+
+        // enable frame skip
+        // gb.assume_init().direct.set_frame_skip(!true); // active low
+    };
+
+    loop {
+        let event = get_key();
+        let button = match event.key {
+            KeyCode::Esc => {
+                unsafe { write_save(&mut gb.assume_init()) };
+                break;
+            }
+            KeyCode::Char('r') => {
+                unsafe { gb_reset(gb.as_mut_ptr()) };
+                continue;
+            }
+            KeyCode::Tab => JOYPAD_START as u8,
+            KeyCode::Del => JOYPAD_SELECT as u8,
+            KeyCode::Enter => JOYPAD_A as u8,
+            KeyCode::Backspace => JOYPAD_B as u8,
+            KeyCode::Up => JOYPAD_UP as u8,
+            KeyCode::Down => JOYPAD_DOWN as u8,
+            KeyCode::Left => JOYPAD_LEFT as u8,
+            KeyCode::Right => JOYPAD_RIGHT as u8,
+            _ => 0,
+        };
+
+        if button != 0 {
+            unsafe {
+                // bindgen incorrectly generates direct so manual manipulation is required :(
+                let direct_ptr = &mut gb.assume_init().direct as *mut _ as *mut u8;
+                let joypad_ptr = direct_ptr.add(2); // this is the joypad bitfield byte
+
+                if let KeyState::Pressed = event.state {
+                    *joypad_ptr &= !button;
+                } else if let KeyState::Released = event.state {
+                    *joypad_ptr |= button;
+                }
+
+                println!("joypad: {:b}", *joypad_ptr);
+            }
+        }
+
+        unsafe {
+            gb_run_frame(gb.as_mut_ptr());
+        }
+    }
+}
+
+unsafe fn load_save(gb: &mut gb_s) {
+    let mut buf = [0; 16];
+
+    unsafe {
+        gb_get_rom_name(gb, buf.as_mut_ptr());
+
+        let save_size = gb_get_save_size(gb);
+
+        if save_size > 0 {
+            read_file(
+                &format!(
+                    "{}/saves/{}.sav",
+                    GAME_PATH,
+                    str::from_utf8(&buf).expect("bad rom name")
+                ),
+                0,
+                &mut RAM,
+            );
+        }
+    }
+}
+
+unsafe fn write_save(gb: &mut gb_s) {
+    let mut buf = [0; 16];
+
+    unsafe {
+        gb_get_rom_name(gb, buf.as_mut_ptr());
+
+        let save_size = gb_get_save_size(gb);
+
+        if save_size > 0 {
+            write_file(
+                &format!(
+                    "{}/saves/{}.sav",
+                    GAME_PATH,
+                    str::from_utf8(&buf).expect("bad rom name")
+                ),
+                0,
+                &mut RAM,
+            );
+        }
+    }
+}

user_apps/gboy/src/peanut.rs

@@ -0,0 +1,102 @@
+#![allow(non_upper_case_globals)]
+#![allow(non_camel_case_types)]
+#![allow(non_snake_case)]
+
+use crate::{DISPLAY, GAME_ROM, RAM};
+
+#[allow(unused)]
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
+
+use embedded_graphics::{pixelcolor::Rgb565, prelude::Point, Drawable};
+use userlib::{display::Pixel565, println};
+
+pub const GBOY_WIDTH: usize = 160;
+pub const GBOY_HEIGHT: usize = 144;
+
+pub unsafe extern "C" fn gb_rom_read(_gb: *mut gb_s, addr: u32) -> u8 {
+    unsafe { GAME_ROM.as_ref().unwrap()[addr as usize] }
+}
+
+pub unsafe extern "C" fn gb_cart_ram_read(_gb: *mut gb_s, addr: u32) -> u8 {
+    unsafe { RAM[addr as usize] }
+}
+
+pub unsafe extern "C" fn gb_cart_ram_write(_gb: *mut gb_s, addr: u32, val: u8) {
+    unsafe { RAM[addr as usize] = val }
+}
+
+pub unsafe extern "C" fn gb_error(_gb: *mut gb_s, err: gb_error_e, addr: u16) {
+    let e = match err {
+        0 => "UNKNOWN ERROR",
+        1 => "INVALID OPCODE",
+        2 => "INVALID READ",
+        3 => "INVALID WRITE",
+        4 => "HALT FOREVER",
+        5 => "INVALID MAX",
+        _ => unreachable!(),
+    };
+
+    println!("PeanutGB error: {}, addr: {}", e, addr);
+}
+
+const NUM_PALETTES: usize = 3;
+const SHADES_PER_PALETTE: usize = 4;
+
+const PALETTES: [[Rgb565; SHADES_PER_PALETTE]; NUM_PALETTES] = [
+    [
+        Rgb565::new(8, 24, 32),
+        Rgb565::new(52, 104, 86),
+        Rgb565::new(136, 192, 112),
+        Rgb565::new(224, 248, 208),
+    ], // BG
+    [
+        Rgb565::new(8, 24, 32),
+        Rgb565::new(52, 104, 86),
+        Rgb565::new(136, 192, 112),
+        Rgb565::new(224, 248, 208),
+    ], // OBJ0
+    [
+        Rgb565::new(8, 24, 32),
+        Rgb565::new(52, 104, 86),
+        Rgb565::new(136, 192, 112),
+        Rgb565::new(224, 248, 208),
+    ], // OBJ1
+];
+
+pub unsafe extern "C" fn lcd_draw_line(_gb: *mut gb_s, pixels: *const u8, line: u8) {
+    if line < GBOY_HEIGHT as u8 {
+        let pixels = unsafe { core::slice::from_raw_parts(pixels, GBOY_WIDTH) };
+        let y = line as u16;
+
+        for (x, &p) in pixels.iter().enumerate() {
+            let palette_idx = ((p & 0xF0) >> 4) as usize;
+            let shade_idx = (p & 0x03) as usize;
+
+            let color = PALETTES
+                .get(palette_idx)
+                .and_then(|pal| pal.get(shade_idx))
+                .copied()
+                .unwrap_or(Rgb565::new(0, 0, 0));
+
+            // let sx = (x as u16) * 2;
+            // let sy = y * 2;
+
+            // draw_color(color, sx, sy);
+            // draw_color(color, sx + 1, sy);
+            // draw_color(color, sx, sy + 1);
+            // draw_color(color, sx + 1, sy + 1);
+            //
+            draw_color(color, x as u16, y as u16);
+        }
+    }
+}
+
+fn draw_color(color: Rgb565, x: u16, y: u16) {
+    let mut pixel = Pixel565::default();
+    pixel.0 = Point::new(x.into(), y.into());
+    pixel.1 = color;
+
+    unsafe {
+        pixel.draw(&mut *DISPLAY).unwrap();
+    }
+}

user_apps/gif/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "gif"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+selection_ui = { path = "../../selection_ui" }
+embedded-graphics = "0.8.1"
+tinygif = { git = "https://github.com/LegitCamper/tinygif" }

user_apps/gif/build.rs

@@ -0,0 +1,28 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}

user_apps/gif/src/main.rs

@@ -0,0 +1,98 @@
+#![no_std]
+#![no_main]
+
+extern crate alloc;
+use alloc::{format, vec, vec::Vec};
+use core::panic::PanicInfo;
+use embedded_graphics::{
+    image::ImageDrawable,
+    mono_font::{MonoTextStyle, ascii::FONT_6X10},
+    pixelcolor::Rgb565,
+    prelude::{Point, RgbColor},
+    transform::Transform,
+};
+use selection_ui::{SelectionUi, SelectionUiError, draw_text_center};
+use tinygif::Gif;
+use userlib::{
+    display::{Display, SCREEN_HEIGHT, SCREEN_WIDTH},
+    fs::{Entries, file_len, list_dir, read_file},
+    get_key, get_ms,
+    keyboard::{KeyCode, KeyState},
+    println, sleep,
+};
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location(),);
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+pub fn main() {
+    println!("Starting Gif app");
+    let mut display = Display::take().unwrap();
+
+    let mut entries = Entries::new();
+    list_dir("/gifs", &mut entries);
+
+    let mut files = entries.entries();
+    files.retain(|e| e.extension().unwrap_or("") == "gif");
+    let mut gifs = files.iter().map(|e| e.full_name()).collect::<Vec<&str>>();
+    gifs.sort();
+
+    let mut selection_ui = SelectionUi::new(&gifs);
+    let selection = match selection_ui.run_selection_ui(&mut display) {
+        Ok(maybe_sel) => maybe_sel,
+        Err(e) => match e {
+            SelectionUiError::SelectionListEmpty => {
+                draw_text_center(
+                    &mut display,
+                    "No Gifs were found in /gifs",
+                    MonoTextStyle::new(&FONT_6X10, Rgb565::RED),
+                )
+                .expect("Display Error");
+                None
+            }
+            SelectionUiError::DisplayError(_) => panic!("Display Error"),
+        },
+    };
+
+    assert!(selection.is_some());
+
+    let file_name = format!("/gifs/{}", gifs[selection.unwrap()]);
+    let size = file_len(&file_name);
+    let mut buf = vec![0_u8; size];
+    let read = read_file(&file_name, 0, &mut buf);
+    println!("read: {}, file size: {}", read, size);
+    assert!(read == size);
+
+    let gif = Gif::<Rgb565>::from_slice(&buf).expect("Failed to parse gif");
+
+    let translation = Point::new(
+        (SCREEN_WIDTH as i32 - gif.width() as i32) / 2,
+        (SCREEN_HEIGHT as i32 - gif.height() as i32) / 2,
+    );
+
+    let mut frame_num = 0;
+    loop {
+        for mut frame in gif.frames() {
+            let start = get_ms();
+
+            frame.translate_mut(translation).draw(&mut display).unwrap();
+            frame_num += 1;
+
+            if frame_num % 5 == 0 {
+                let event = get_key();
+                if event.state != KeyState::Idle && event.key == KeyCode::Esc {
+                    drop(buf);
+                    return;
+                };
+            }
+            sleep(((frame.delay_centis as u64) * 10).saturating_sub(start));
+        }
+    }
+}

user_apps/memory.x

@@ -0,0 +1,31 @@
+MEMORY
+{
+  RAM : ORIGIN = 0x0, LENGTH = 250K
+}
+
+SECTIONS
+{
+  .text : ALIGN(4)
+  {
+      *(.text .text.*);
+      *(.rodata .rodata.*);
+  } > RAM
+
+  .data : ALIGN(4)
+  {
+      *(.data .data.*);
+  } > RAM
+
+  .bss : ALIGN(4)
+  {
+      *(.bss .bss.*);
+      *(COMMON);
+  } > RAM
+
+  .syscall_table (NOLOAD) : ALIGN(4)
+  {
+      __user_reloc_start = .;
+      KEEP(*(.user_reloc*));
+      __user_reloc_end = .;
+  } > RAM
+}

user_apps/snake/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "snake"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+embedded-graphics = "0.8.1"
+embedded-snake = { git = "https://github.com/LegitCamper/embedded-snake-rs" }
+rand = { version = "0.9.0", default-features = false }

user_apps/snake/build.rs

@@ -0,0 +1,28 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}

user_apps/snake/src/main.rs

@@ -0,0 +1,65 @@
+#![no_std]
+#![no_main]
+
+extern crate alloc;
+use core::panic::PanicInfo;
+use embedded_graphics::{pixelcolor::Rgb565, prelude::RgbColor};
+use embedded_snake::{Direction, SnakeGame};
+use userlib::{
+    Rng,
+    display::{Display, SCREEN_HEIGHT, SCREEN_WIDTH},
+    get_key,
+    keyboard::{KeyCode, KeyState},
+    println, sleep,
+};
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location(),);
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+const CELL_SIZE: usize = 8;
+
+pub fn main() {
+    println!("Starting Snake app");
+    let mut display = Display::take().unwrap();
+
+    let mut game = SnakeGame::<100, Rgb565, Rng>::new(
+        SCREEN_WIDTH as u16,
+        SCREEN_HEIGHT as u16,
+        CELL_SIZE as u16,
+        CELL_SIZE as u16,
+        Rng,
+        Rgb565::BLACK,
+        Rgb565::GREEN,
+        Rgb565::RED,
+        50,
+    );
+
+    loop {
+        let event = get_key();
+        if event.state != KeyState::Idle {
+            let direction = match event.key {
+                KeyCode::Up => Direction::Up,
+                KeyCode::Down => Direction::Down,
+                KeyCode::Right => Direction::Right,
+                KeyCode::Left => Direction::Left,
+                KeyCode::Esc => return,
+                _ => Direction::None,
+            };
+            game.set_direction(direction);
+        };
+
+        // ensure all draws show up at once
+        game.pre_draw(&mut display);
+        game.draw(&mut display);
+
+        sleep(15);
+    }
+}

user_apps/wav_player/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "wav_player"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+selection_ui = { path = "../../selection_ui" }
+embedded-graphics = "0.8.1"
+rand = { version = "0.9.0", default-features = false }
+embedded-audio = { git = "https://github.com/LegitCamper/embedded-audio" }

user_apps/wav_player/build.rs

@@ -0,0 +1,28 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}

user_apps/wav_player/src/main.rs

@@ -0,0 +1,143 @@
+#![no_std]
+#![no_main]
+
+extern crate alloc;
+use alloc::{string::String, vec::Vec};
+use core::panic::PanicInfo;
+use embedded_audio::{AudioFile, PlatformFile, PlatformFileError, wav::Wav};
+use embedded_graphics::{
+    mono_font::{MonoTextStyle, ascii::FONT_6X10},
+    pixelcolor::Rgb565,
+    prelude::RgbColor,
+};
+use selection_ui::{SelectionUi, SelectionUiError, draw_text_center};
+use userlib::{
+    audio::{AUDIO_BUFFER_LEN, audio_buffer_ready, send_audio_buffer},
+    display::Display,
+    format,
+    fs::{Entries, file_len, list_dir, read_file},
+    get_key,
+    keyboard::{KeyCode, KeyState},
+    println,
+};
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location(),);
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+pub fn main() {
+    println!("Starting Wav player app");
+    let mut display = Display::take().unwrap();
+
+    loop {
+        let mut entries = Entries::new();
+        list_dir("/music", &mut entries);
+
+        let mut files = entries.entries();
+        files.retain(|e| e.extension().unwrap_or("") == "wav");
+        let mut wavs = files.iter().map(|e| e.full_name()).collect::<Vec<&str>>();
+        wavs.sort();
+
+        let mut selection_ui = SelectionUi::new(&wavs);
+        let selection = match selection_ui.run_selection_ui(&mut display) {
+            Ok(maybe_sel) => maybe_sel,
+            Err(e) => match e {
+                SelectionUiError::SelectionListEmpty => {
+                    draw_text_center(
+                        &mut display,
+                        "No Wavs were found in /music",
+                        MonoTextStyle::new(&FONT_6X10, Rgb565::RED),
+                    )
+                    .expect("Display Error");
+                    None
+                }
+                SelectionUiError::DisplayError(_) => panic!("Display Error"),
+            },
+        };
+
+        assert!(selection.is_some());
+
+        draw_text_center(
+            &mut display,
+            &format!("Now playing {}", wavs[selection.unwrap()]),
+            MonoTextStyle::new(&FONT_6X10, Rgb565::WHITE),
+        )
+        .expect("Display Error");
+
+        let file_name = format!("/music/{}", wavs[selection.unwrap()]);
+        let file = File::new(file_name);
+        let mut wav = Wav::new(file).unwrap();
+        println!("sample rate: {}", wav.sample_rate());
+        println!("channels: {:?}", wav.channels() as u8);
+
+        let mut buf = [0_u8; AUDIO_BUFFER_LEN];
+
+        loop {
+            if audio_buffer_ready() {
+                if wav.is_eof() {
+                    break;
+                }
+
+                let _read = wav.read(&mut buf).unwrap();
+                send_audio_buffer(&buf);
+            }
+
+            let event = get_key();
+            if event.state == KeyState::Released && event.key == KeyCode::Esc {
+                return;
+            }
+        }
+    }
+}
+
+struct File {
+    current_pos: usize,
+    file: String,
+}
+
+impl File {
+    fn new(file: String) -> Self {
+        Self {
+            current_pos: 0,
+            file,
+        }
+    }
+}
+
+impl PlatformFile for File {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, PlatformFileError> {
+        let read = read_file(&self.file, self.current_pos, buf);
+        self.current_pos += read;
+        Ok(read)
+    }
+
+    fn seek_from_current(&mut self, offset: i64) -> Result<(), PlatformFileError> {
+        if offset.is_positive() {
+            self.current_pos += offset as usize;
+        } else {
+            self.current_pos -= offset as usize;
+        }
+        Ok(())
+    }
+
+    fn seek_from_start(&mut self, offset: usize) -> Result<(), PlatformFileError> {
+        self.current_pos = offset;
+        Ok(())
+    }
+
+    fn seek_from_end(&mut self, offset: usize) -> Result<(), PlatformFileError> {
+        self.current_pos = self.length() - offset;
+        Ok(())
+    }
+
+    fn length(&mut self) -> usize {
+        file_len(&self.file)
+    }
+}