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feat: add 0x08_lcd1602_rust driver with 14 unit tests

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Kevin Thomas
2026-03-25 17:31:05 -04:00
parent b0299bf95e
commit c68e158f16
18 changed files with 1639 additions and 0 deletions
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1
README.md
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@@ -530,6 +530,7 @@ cargo test --lib --target x86_64-pc-windows-msvc
| [0x05_servo_rust](drivers/0x05_servo_rust) | SG90 servo motor control | `rp235x-hal`, `embedded-hal` |
| [0x06_adc_rust](drivers/0x06_adc_rust) | 12-bit ADC voltage + temperature | `rp235x-hal`, `embedded-hal` |
| [0x07_i2c_rust](drivers/0x07_i2c_rust) | I2C bus scanner (7-bit addresses) | `rp235x-hal`, `embedded-hal` |
| [0x08_lcd1602_rust](drivers/0x08_lcd1602_rust) | HD44780 16x2 LCD (PCF8574 I2C) | `rp235x-hal`, `embedded-hal` |
<br>

102
drivers/0x08_lcd1602_rust/.cargo/config.toml Normal file
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@@ -0,0 +1,102 @@
# SPDX-License-Identifier: MIT OR Apache-2.0
#
# Copyright (c) 2021–2024 The rp-rs Developers
# Copyright (c) 2021 rp-rs organization
# Copyright (c) 2025 Raspberry Pi Ltd.
#
# Cargo Configuration for the https://github.com/rp-rs/rp-hal.git repository.
#
# You might want to make a similar file in your own repository if you are
# writing programs for Raspberry Silicon microcontrollers.
#
[build]
target = "thumbv8m.main-none-eabihf"
# Set the default target to match the Cortex-M33 in the RP2350
# target = "thumbv8m.main-none-eabihf"
# target = "thumbv6m-none-eabi"
# target = "riscv32imac-unknown-none-elf"
# Target specific options
[target.thumbv6m-none-eabi]
# Pass some extra options to rustc, some of which get passed on to the linker.
#
# * linker argument --nmagic turns off page alignment of sections (which saves
# flash space)
# * linker argument -Tlink.x tells the linker to use link.x as the linker
# script. This is usually provided by the cortex-m-rt crate, and by default
# the version in that crate will include a file called `memory.x` which
# describes the particular memory layout for your specific chip.
# * no-vectorize-loops turns off the loop vectorizer (seeing as the M0+ doesn't
# have SIMD)
linker = "flip-link"
rustflags = [
"-C", "link-arg=--nmagic",
"-C", "link-arg=-Tlink.x",
"-C", "link-arg=-Tdefmt.x",
"-C", "no-vectorize-loops",
]
# Use picotool for loading.
#
# Load an elf, skipping unchanged flash sectors, verify it, and execute it
runner = "${PICOTOOL_PATH} load -u -v -x -t elf"
#runner = "probe-rs run --chip ${CHIP} --protocol swd"
# This is the hard-float ABI for Arm mode.
#
# The FPU is enabled by default, and float function arguments use FPU
# registers.
[target.thumbv8m.main-none-eabihf]
# Pass some extra options to rustc, some of which get passed on to the linker.
#
# * linker argument --nmagic turns off page alignment of sections (which saves
# flash space)
# * linker argument -Tlink.x tells the linker to use link.x as a linker script.
# This is usually provided by the cortex-m-rt crate, and by default the
# version in that crate will include a file called `memory.x` which describes
# the particular memory layout for your specific chip.
# * linker argument -Tdefmt.x also tells the linker to use `defmt.x` as a
# secondary linker script. This is required to make defmt_rtt work.
rustflags = [
"-C", "link-arg=--nmagic",
"-C", "link-arg=-Tlink.x",
"-C", "link-arg=-Tdefmt.x",
"-C", "target-cpu=cortex-m33",
]
# Use picotool for loading.
#
# Load an elf, skipping unchanged flash sectors, verify it, and execute it
runner = "${PICOTOOL_PATH} load -u -v -x -t elf"
#runner = "probe-rs run --chip ${CHIP} --protocol swd"
# This is the soft-float ABI for RISC-V mode.
#
# Hazard 3 does not have an FPU and so float function arguments use integer
# registers.
[target.riscv32imac-unknown-none-elf]
# Pass some extra options to rustc, some of which get passed on to the linker.
#
# * linker argument --nmagic turns off page alignment of sections (which saves
# flash space)
# * linker argument -Trp235x_riscv.x also tells the linker to use
# `rp235x_riscv.x` as a linker script. This adds in RP2350 RISC-V specific
# things that the riscv-rt crate's `link.x` requires and then includes
# `link.x` automatically. This is the reverse of how we do it on Cortex-M.
# * linker argument -Tdefmt.x also tells the linker to use `defmt.x` as a
# secondary linker script. This is required to make defmt_rtt work.
rustflags = [
"-C", "link-arg=--nmagic",
"-C", "link-arg=-Trp2350_riscv.x",
"-C", "link-arg=-Tdefmt.x",
]
# Use picotool for loading.
#
# Load an elf, skipping unchanged flash sectors, verify it, and execute it
runner = "${PICOTOOL_PATH} load -u -v -x -t elf"
#runner = "probe-rs run --chip ${CHIP} --protocol swd"
[env]
DEFMT_LOG = "debug"

113
drivers/0x08_lcd1602_rust/.gitignore vendored Normal file
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@@ -0,0 +1,113 @@
# Created by https://www.toptal.com/developers/gitignore/api/rust,visualstudiocode,macos,windows,linux
# Edit at https://www.toptal.com/developers/gitignore?templates=rust,visualstudiocode,macos,windows,linux
### Linux ###
*~
# temporary files which can be created if a process still has a handle open of a deleted file
.fuse_hidden*
# KDE directory preferences
.directory
# Linux trash folder which might appear on any partition or disk
.Trash-*
# .nfs files are created when an open file is removed but is still being accessed
.nfs*
### macOS ###
# General
.DS_Store
.AppleDouble
.LSOverride
# Icon must end with two
Icon
# Thumbnails
._*
# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns
.com.apple.timemachine.donotpresent
# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk
### macOS Patch ###
# iCloud generated files
*.icloud
### Rust ###
# Generated by Cargo
# will have compiled files and executables
debug/
target/
# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
Cargo.lock
# These are backup files generated by rustfmt
**/*.rs.bk
# MSVC Windows builds of rustc generate these, which store debugging information
*.pdb
### VisualStudioCode ###
.vscode/*
!.vscode/settings.json
!.vscode/tasks.json
!.vscode/launch.json
!.vscode/extensions.json
!.vscode/*.code-snippets
# Local History for Visual Studio Code
.history/
# Built Visual Studio Code Extensions
*.vsix
### VisualStudioCode Patch ###
# Ignore all local history of files
.history
.ionide
### Windows ###
# Windows thumbnail cache files
Thumbs.db
Thumbs.db:encryptable
ehthumbs.db
ehthumbs_vista.db
# Dump file
*.stackdump
# Folder config file
[Dd]esktop.ini
# Recycle Bin used on file shares
$RECYCLE.BIN/
# Windows Installer files
*.cab
*.msi
*.msix
*.msm
*.msp
# Windows shortcuts
*.lnk
# End of https://www.toptal.com/developers/gitignore/api/rust,visualstudiocode,macos,windows,linux

1
drivers/0x08_lcd1602_rust/.pico-rs Normal file
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@@ -0,0 +1 @@
rp2350

8
drivers/0x08_lcd1602_rust/.vscode/extensions.json vendored Normal file
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@@ -0,0 +1,8 @@
{
"recommendations": [
"marus25.cortex-debug",
"rust-lang.rust-analyzer",
"probe-rs.probe-rs-debugger",
"raspberry-pi.raspberry-pi-pico"
]
}

41
drivers/0x08_lcd1602_rust/.vscode/launch.json vendored Normal file
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@@ -0,0 +1,41 @@
{
"version": "0.2.0",
"configurations": [
{
"name": "Pico Debug (probe-rs)",
"cwd": "${workspaceFolder}",
"request": "launch",
"type": "probe-rs-debug",
"connectUnderReset": false,
"speed": 5000,
"runtimeExecutable": "probe-rs",
"chip": "${command:raspberry-pi-pico.getChip}",
"runtimeArgs": [
"dap-server"
],
"flashingConfig": {
"flashingEnabled": true,
"haltAfterReset": false
},
"coreConfigs": [
{
"coreIndex": 0,
"programBinary": "${command:raspberry-pi-pico.launchTargetPath}",
"rttEnabled": true,
"svdFile": "${command:raspberry-pi-pico.getSVDPath}",
"rttChannelFormats": [
{
"channelNumber": 0,
"dataFormat": "Defmt",
"mode": "NoBlockSkip",
"showTimestamps": true
}
]
}
],
"preLaunchTask": "Build + Generate SBOM (debug)",
"consoleLogLevel": "Debug",
"wireProtocol": "Swd"
}
]
}

8
drivers/0x08_lcd1602_rust/.vscode/settings.json vendored Normal file
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@@ -0,0 +1,8 @@
{
"rust-analyzer.cargo.target": "thumbv8m.main-none-eabihf",
"rust-analyzer.check.allTargets": false,
"editor.formatOnSave": true,
"files.exclude": {
".pico-rs": true
}
}

124
drivers/0x08_lcd1602_rust/.vscode/tasks.json vendored Normal file
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@@ -0,0 +1,124 @@
{
"version": "2.0.0",
"tasks": [
{
"label": "Compile Project",
"type": "process",
"isBuildCommand": true,
"command": "cargo",
"args": [
"build",
"--release"
],
"group": {
"kind": "build",
"isDefault": true
},
"presentation": {
"reveal": "always",
"panel": "dedicated"
},
"problemMatcher": "$rustc",
"options": {
"env": {
"PICOTOOL_PATH": "${command:raspberry-pi-pico.getPicotoolPath}",
"CHIP": "${command:raspberry-pi-pico.getChip}"
}
}
},
{
"label": "Build + Generate SBOM (release)",
"type": "shell",
"command": "bash",
"args": [
"-lc",
"cargo sbom > ${command:raspberry-pi-pico.sbomTargetPathRelease}"
],
"windows": {
"command": "powershell",
"args": [
"-NoProfile",
"-ExecutionPolicy",
"Bypass",
"-Command",
"cargo sbom | Set-Content -Encoding utf8 ${command:raspberry-pi-pico.sbomTargetPathRelease}"
]
},
"dependsOn": "Compile Project",
"presentation": {
"reveal": "silent",
"panel": "shared"
},
"problemMatcher": []
},
{
"label": "Compile Project (debug)",
"type": "process",
"isBuildCommand": true,
"command": "cargo",
"args": [
"build"
],
"group": {
"kind": "build",
"isDefault": false
},
"presentation": {
"reveal": "always",
"panel": "dedicated"
},
"problemMatcher": "$rustc",
"options": {
"env": {
"PICOTOOL_PATH": "${command:raspberry-pi-pico.getPicotoolPath}",
"CHIP": "${command:raspberry-pi-pico.getChip}"
}
}
},
{
"label": "Build + Generate SBOM (debug)",
"type": "shell",
"command": "bash",
"args": [
"-lc",
"cargo sbom > ${command:raspberry-pi-pico.sbomTargetPathDebug}"
],
"windows": {
"command": "powershell",
"args": [
"-NoProfile",
"-ExecutionPolicy",
"Bypass",
"-Command",
"cargo sbom | Set-Content -Encoding utf8 ${command:raspberry-pi-pico.sbomTargetPathDebug}"
]
},
"dependsOn": "Compile Project (debug)",
"presentation": {
"reveal": "silent",
"panel": "shared"
},
"problemMatcher": []
},
{
"label": "Run Project",
"type": "shell",
"dependsOn": [
"Build + Generate SBOM (release)"
],
"command": "${command:raspberry-pi-pico.getPicotoolPath}",
"args": [
"load",
"-x",
"${command:raspberry-pi-pico.launchTargetPathRelease}",
"-t",
"elf"
],
"presentation": {
"reveal": "always",
"panel": "dedicated"
},
"problemMatcher": []
}
]
}

40
drivers/0x08_lcd1602_rust/Cargo.toml Normal file
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@@ -0,0 +1,40 @@
[package]
edition = "2024"
name = "lcd1602"
version = "0.1.0"
license = "MIT or Apache-2.0"
[lib]
name = "lcd1602_lib"
path = "src/lib.rs"
[[bin]]
name = "lcd1602"
path = "src/main.rs"
[build-dependencies]
regex = "1.11.0"
[dependencies]
cortex-m = "0.7"
cortex-m-rt = "0.7"
embedded-hal = "1.0.0"
fugit = "0.3"
defmt = "1"
defmt-rtt = "1"
[target.'cfg( target_arch = "arm" )'.dependencies]
panic-probe = { version = "1", features = ["print-defmt"] }
[target.'cfg( target_arch = "riscv32" )'.dependencies]
panic-halt = { version = "1.0.0" }
[target.thumbv6m-none-eabi.dependencies]
rp2040-boot2 = "0.3"
rp2040-hal = { version = "0.11", features = ["rt", "critical-section-impl"] }
[target.riscv32imac-unknown-none-elf.dependencies]
rp235x-hal = { version = "0.3", features = ["rt", "critical-section-impl"] }
[target."thumbv8m.main-none-eabihf".dependencies]
rp235x-hal = { version = "0.3", features = ["rt", "critical-section-impl"] }

204
drivers/0x08_lcd1602_rust/LICENSE-APACHE Normal file
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@@ -0,0 +1,204 @@
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Copyright (c) 2021–2024 The rp-rs Developers
Copyright (c) 2021 rp-rs organization
Copyright (c) 2025 Raspberry Pi Ltd.
Licensed under the Apache License, Version 2.0 (the "License");
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drivers/0x08_lcd1602_rust/LICENSE-MIT Normal file
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@@ -0,0 +1,24 @@
MIT License
Copyright (c) 2021–2024 The rp-rs Developers
Copyright (c) 2021 rp-rs organization
Copyright (c) 2025 Raspberry Pi Ltd.
Permission is hereby granted, free of charge, to any person obtaining a copy
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SOFTWARE.

68
drivers/0x08_lcd1602_rust/build.rs Normal file
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//! SPDX-License-Identifier: MIT OR Apache-2.0
//!
//! Copyright (c) 2021–2024 The rp-rs Developers
//! Copyright (c) 2021 rp-rs organization
//! Copyright (c) 2025 Raspberry Pi Ltd.
//!
//! Set up linker scripts
use std::fs::{ File, read_to_string };
use std::io::Write;
use std::path::PathBuf;
use regex::Regex;
fn main() {
println!("cargo::rustc-check-cfg=cfg(rp2040)");
println!("cargo::rustc-check-cfg=cfg(rp2350)");
// Put the linker script somewhere the linker can find it
let out = PathBuf::from(std::env::var_os("OUT_DIR").unwrap());
println!("cargo:rustc-link-search={}", out.display());
println!("cargo:rerun-if-changed=.pico-rs");
let contents = read_to_string(".pico-rs")
.map(|s| s.trim().to_string().to_lowercase())
.unwrap_or_else(|e| {
eprintln!("Failed to read file: {}", e);
String::new()
});
// The file `memory.x` is loaded by cortex-m-rt's `link.x` script, which
// is what we specify in `.cargo/config.toml` for Arm builds
let target;
if contents == "rp2040" {
target = "thumbv6m-none-eabi";
let memory_x = include_bytes!("rp2040.x");
let mut f = File::create(out.join("memory.x")).unwrap();
f.write_all(memory_x).unwrap();
println!("cargo::rustc-cfg=rp2040");
println!("cargo:rerun-if-changed=rp2040.x");
} else {
if contents.contains("riscv") {
target = "riscv32imac-unknown-none-elf";
} else {
target = "thumbv8m.main-none-eabihf";
}
let memory_x = include_bytes!("rp2350.x");
let mut f = File::create(out.join("memory.x")).unwrap();
f.write_all(memory_x).unwrap();
println!("cargo::rustc-cfg=rp2350");
println!("cargo:rerun-if-changed=rp2350.x");
}
let re = Regex::new(r"target = .*").unwrap();
let config_toml = include_str!(".cargo/config.toml");
let result = re.replace(config_toml, format!("target = \"{}\"", target));
let mut f = File::create(".cargo/config.toml").unwrap();
f.write_all(result.as_bytes()).unwrap();
// The file `rp2350_riscv.x` is what we specify in `.cargo/config.toml` for
// RISC-V builds
let rp2350_riscv_x = include_bytes!("rp2350_riscv.x");
let mut f = File::create(out.join("rp2350_riscv.x")).unwrap();
f.write_all(rp2350_riscv_x).unwrap();
println!("cargo:rerun-if-changed=rp2350_riscv.x");
println!("cargo:rerun-if-changed=build.rs");
}

91
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/*
* SPDX-License-Identifier: MIT OR Apache-2.0
*
* Copyright (c) 2021–2024 The rp-rs Developers
* Copyright (c) 2021 rp-rs organization
* Copyright (c) 2025 Raspberry Pi Ltd.
*/
MEMORY {
BOOT2 : ORIGIN = 0x10000000, LENGTH = 0x100
/*
* Here we assume you have 2048 KiB of Flash. This is what the Pi Pico
* has, but your board may have more or less Flash and you should adjust
* this value to suit.
*/
FLASH : ORIGIN = 0x10000100, LENGTH = 2048K - 0x100
/*
* RAM consists of 4 banks, SRAM0-SRAM3, with a striped mapping.
* This is usually good for performance, as it distributes load on
* those banks evenly.
*/
RAM : ORIGIN = 0x20000000, LENGTH = 256K
/*
* RAM banks 4 and 5 use a direct mapping. They can be used to have
* memory areas dedicated for some specific job, improving predictability
* of access times.
* Example: Separate stacks for core0 and core1.
*/
SRAM4 : ORIGIN = 0x20040000, LENGTH = 4k
SRAM5 : ORIGIN = 0x20041000, LENGTH = 4k
/* SRAM banks 0-3 can also be accessed directly. However, those ranges
alias with the RAM mapping, above. So don't use them at the same time!
SRAM0 : ORIGIN = 0x21000000, LENGTH = 64k
SRAM1 : ORIGIN = 0x21010000, LENGTH = 64k
SRAM2 : ORIGIN = 0x21020000, LENGTH = 64k
SRAM3 : ORIGIN = 0x21030000, LENGTH = 64k
*/
}
EXTERN(BOOT2_FIRMWARE)
SECTIONS {
/* ### Boot loader
*
* An executable block of code which sets up the QSPI interface for
* 'Execute-In-Place' (or XIP) mode. Also sends chip-specific commands to
* the external flash chip.
*
* Must go at the start of external flash, where the Boot ROM expects it.
*/
.boot2 ORIGIN(BOOT2) :
{
KEEP(*(.boot2));
} > BOOT2
} INSERT BEFORE .text;
SECTIONS {
/* ### Boot ROM info
*
* Goes after .vector_table, to keep it in the first 512 bytes of flash,
* where picotool can find it
*/
.boot_info : ALIGN(4)
{
KEEP(*(.boot_info));
} > FLASH
} INSERT AFTER .vector_table;
/* move .text to start /after/ the boot info */
_stext = ADDR(.boot_info) + SIZEOF(.boot_info);
SECTIONS {
/* ### Picotool 'Binary Info' Entries
*
* Picotool looks through this block (as we have pointers to it in our
* header) to find interesting information.
*/
.bi_entries : ALIGN(4)
{
/* We put this in the header */
__bi_entries_start = .;
/* Here are the entries */
KEEP(*(.bi_entries));
/* Keep this block a nice round size */
. = ALIGN(4);
/* We put this in the header */
__bi_entries_end = .;
} > FLASH
} INSERT AFTER .text;

83
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/*
* SPDX-License-Identifier: MIT OR Apache-2.0
*
* Copyright (c) 2021–2024 The rp-rs Developers
* Copyright (c) 2021 rp-rs organization
* Copyright (c) 2025 Raspberry Pi Ltd.
*/
MEMORY {
/*
* The RP2350 has either external or internal flash.
*
* 2 MiB is a safe default here, although a Pico 2 has 4 MiB.
*/
FLASH : ORIGIN = 0x10000000, LENGTH = 2048K
/*
* RAM consists of 8 banks, SRAM0-SRAM7, with a striped mapping.
* This is usually good for performance, as it distributes load on
* those banks evenly.
*/
RAM : ORIGIN = 0x20000000, LENGTH = 512K
/*
* RAM banks 8 and 9 use a direct mapping. They can be used to have
* memory areas dedicated for some specific job, improving predictability
* of access times.
* Example: Separate stacks for core0 and core1.
*/
SRAM4 : ORIGIN = 0x20080000, LENGTH = 4K
SRAM5 : ORIGIN = 0x20081000, LENGTH = 4K
}
SECTIONS {
/* ### Boot ROM info
*
* Goes after .vector_table, to keep it in the first 4K of flash
* where the Boot ROM (and picotool) can find it
*/
.start_block : ALIGN(4)
{
__start_block_addr = .;
KEEP(*(.start_block));
} > FLASH
} INSERT AFTER .vector_table;
/* move .text to start /after/ the boot info */
_stext = ADDR(.start_block) + SIZEOF(.start_block);
SECTIONS {
/* ### Picotool 'Binary Info' Entries
*
* Picotool looks through this block (as we have pointers to it in our
* header) to find interesting information.
*/
.bi_entries : ALIGN(4)
{
/* We put this in the header */
__bi_entries_start = .;
/* Here are the entries */
KEEP(*(.bi_entries));
/* Keep this block a nice round size */
. = ALIGN(4);
/* We put this in the header */
__bi_entries_end = .;
} > FLASH
} INSERT AFTER .text;
SECTIONS {
/* ### Boot ROM extra info
*
* Goes after everything in our program, so it can contain a signature.
*/
.end_block : ALIGN(4)
{
__end_block_addr = .;
KEEP(*(.end_block));
} > FLASH
} INSERT AFTER .uninit;
PROVIDE(start_to_end = __end_block_addr - __start_block_addr);
PROVIDE(end_to_start = __start_block_addr - __end_block_addr);

259
drivers/0x08_lcd1602_rust/rp2350_riscv.x Normal file
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/*
* SPDX-License-Identifier: MIT OR Apache-2.0
*
* Copyright (c) 2021–2024 The rp-rs Developers
* Copyright (c) 2021 rp-rs organization
* Copyright (c) 2025 Raspberry Pi Ltd.
*/
MEMORY {
/*
* The RP2350 has either external or internal flash.
*
* 2 MiB is a safe default here, although a Pico 2 has 4 MiB.
*/
FLASH : ORIGIN = 0x10000000, LENGTH = 2048K
/*
* RAM consists of 8 banks, SRAM0-SRAM7, with a striped mapping.
* This is usually good for performance, as it distributes load on
* those banks evenly.
*/
RAM : ORIGIN = 0x20000000, LENGTH = 512K
/*
* RAM banks 8 and 9 use a direct mapping. They can be used to have
* memory areas dedicated for some specific job, improving predictability
* of access times.
* Example: Separate stacks for core0 and core1.
*/
SRAM4 : ORIGIN = 0x20080000, LENGTH = 4K
SRAM5 : ORIGIN = 0x20081000, LENGTH = 4K
}
/* # Developer notes
- Symbols that start with a double underscore (__) are considered "private"
- Symbols that start with a single underscore (_) are considered "semi-public"; they can be
overridden in a user linker script, but should not be referred from user code (e.g. `extern "C" {
static mut _heap_size }`).
- `EXTERN` forces the linker to keep a symbol in the final binary. We use this to make sure a
symbol is not dropped if it appears in or near the front of the linker arguments and "it's not
needed" by any of the preceding objects (linker arguments)
- `PROVIDE` is used to provide default values that can be overridden by a user linker script
- On alignment: it's important for correctness that the VMA boundaries of both .bss and .data *and*
the LMA of .data are all `32`-byte aligned. These alignments are assumed by the RAM
initialization routine. There's also a second benefit: `32`-byte aligned boundaries
means that you won't see "Address (..) is out of bounds" in the disassembly produced by `objdump`.
*/
PROVIDE(_stext = ORIGIN(FLASH));
PROVIDE(_stack_start = ORIGIN(RAM) + LENGTH(RAM));
PROVIDE(_max_hart_id = 0);
PROVIDE(_hart_stack_size = 2K);
PROVIDE(_heap_size = 0);
PROVIDE(InstructionMisaligned = ExceptionHandler);
PROVIDE(InstructionFault = ExceptionHandler);
PROVIDE(IllegalInstruction = ExceptionHandler);
PROVIDE(Breakpoint = ExceptionHandler);
PROVIDE(LoadMisaligned = ExceptionHandler);
PROVIDE(LoadFault = ExceptionHandler);
PROVIDE(StoreMisaligned = ExceptionHandler);
PROVIDE(StoreFault = ExceptionHandler);
PROVIDE(UserEnvCall = ExceptionHandler);
PROVIDE(SupervisorEnvCall = ExceptionHandler);
PROVIDE(MachineEnvCall = ExceptionHandler);
PROVIDE(InstructionPageFault = ExceptionHandler);
PROVIDE(LoadPageFault = ExceptionHandler);
PROVIDE(StorePageFault = ExceptionHandler);
PROVIDE(SupervisorSoft = DefaultHandler);
PROVIDE(MachineSoft = DefaultHandler);
PROVIDE(SupervisorTimer = DefaultHandler);
PROVIDE(MachineTimer = DefaultHandler);
PROVIDE(SupervisorExternal = DefaultHandler);
PROVIDE(MachineExternal = DefaultHandler);
PROVIDE(DefaultHandler = DefaultInterruptHandler);
PROVIDE(ExceptionHandler = DefaultExceptionHandler);
/* # Pre-initialization function */
/* If the user overrides this using the `#[pre_init]` attribute or by creating a `__pre_init` function,
then the function this points to will be called before the RAM is initialized. */
PROVIDE(__pre_init = default_pre_init);
/* A PAC/HAL defined routine that should initialize custom interrupt controller if needed. */
PROVIDE(_setup_interrupts = default_setup_interrupts);
/* # Multi-processing hook function
fn _mp_hook() -> bool;
This function is called from all the harts and must return true only for one hart,
which will perform memory initialization. For other harts it must return false
and implement wake-up in platform-dependent way (e.g. after waiting for a user interrupt).
*/
PROVIDE(_mp_hook = default_mp_hook);
/* # Start trap function override
By default uses the riscv crates default trap handler
but by providing the `_start_trap` symbol external crates can override.
*/
PROVIDE(_start_trap = default_start_trap);
SECTIONS
{
.text.dummy (NOLOAD) :
{
/* This section is intended to make _stext address work */
. = ABSOLUTE(_stext);
} > FLASH
.text _stext :
{
/* Put reset handler first in .text section so it ends up as the entry */
/* point of the program. */
KEEP(*(.init));
KEEP(*(.init.rust));
. = ALIGN(4);
__start_block_addr = .;
KEEP(*(.start_block));
. = ALIGN(4);
*(.trap);
*(.trap.rust);
*(.text.abort);
*(.text .text.*);
. = ALIGN(4);
} > FLASH
/* ### Picotool 'Binary Info' Entries
*
* Picotool looks through this block (as we have pointers to it in our
* header) to find interesting information.
*/
.bi_entries : ALIGN(4)
{
/* We put this in the header */
__bi_entries_start = .;
/* Here are the entries */
KEEP(*(.bi_entries));
/* Keep this block a nice round size */
. = ALIGN(4);
/* We put this in the header */
__bi_entries_end = .;
} > FLASH
.rodata : ALIGN(4)
{
*(.srodata .srodata.*);
*(.rodata .rodata.*);
/* 4-byte align the end (VMA) of this section.
This is required by LLD to ensure the LMA of the following .data
section will have the correct alignment. */
. = ALIGN(4);
} > FLASH
.data : ALIGN(32)
{
_sidata = LOADADDR(.data);
__sidata = LOADADDR(.data);
_sdata = .;
__sdata = .;
/* Must be called __global_pointer$ for linker relaxations to work. */
PROVIDE(__global_pointer$ = . + 0x800);
*(.sdata .sdata.* .sdata2 .sdata2.*);
*(.data .data.*);
. = ALIGN(32);
_edata = .;
__edata = .;
} > RAM AT > FLASH
.bss (NOLOAD) : ALIGN(32)
{
_sbss = .;
*(.sbss .sbss.* .bss .bss.*);
. = ALIGN(32);
_ebss = .;
} > RAM
.end_block : ALIGN(4)
{
__end_block_addr = .;
KEEP(*(.end_block));
} > FLASH
/* fictitious region that represents the memory available for the heap */
.heap (NOLOAD) :
{
_sheap = .;
. += _heap_size;
. = ALIGN(4);
_eheap = .;
} > RAM
/* fictitious region that represents the memory available for the stack */
.stack (NOLOAD) :
{
_estack = .;
. = ABSOLUTE(_stack_start);
_sstack = .;
} > RAM
/* fake output .got section */
/* Dynamic relocations are unsupported. This section is only used to detect
relocatable code in the input files and raise an error if relocatable code
is found */
.got (INFO) :
{
KEEP(*(.got .got.*));
}
.eh_frame (INFO) : { KEEP(*(.eh_frame)) }
.eh_frame_hdr (INFO) : { *(.eh_frame_hdr) }
}
PROVIDE(start_to_end = __end_block_addr - __start_block_addr);
PROVIDE(end_to_start = __start_block_addr - __end_block_addr);
/* Do not exceed this mark in the error messages above | */
ASSERT(ORIGIN(FLASH) % 4 == 0, "
ERROR(riscv-rt): the start of the FLASH must be 4-byte aligned");
ASSERT(ORIGIN(RAM) % 32 == 0, "
ERROR(riscv-rt): the start of the RAM must be 32-byte aligned");
ASSERT(_stext % 4 == 0, "
ERROR(riscv-rt): `_stext` must be 4-byte aligned");
ASSERT(_sdata % 32 == 0 && _edata % 32 == 0, "
BUG(riscv-rt): .data is not 32-byte aligned");
ASSERT(_sidata % 32 == 0, "
BUG(riscv-rt): the LMA of .data is not 32-byte aligned");
ASSERT(_sbss % 32 == 0 && _ebss % 32 == 0, "
BUG(riscv-rt): .bss is not 32-byte aligned");
ASSERT(_sheap % 4 == 0, "
BUG(riscv-rt): start of .heap is not 4-byte aligned");
ASSERT(_stext + SIZEOF(.text) < ORIGIN(FLASH) + LENGTH(FLASH), "
ERROR(riscv-rt): The .text section must be placed inside the FLASH region.
Set _stext to an address smaller than 'ORIGIN(FLASH) + LENGTH(FLASH)'");
ASSERT(SIZEOF(.stack) > (_max_hart_id + 1) * _hart_stack_size, "
ERROR(riscv-rt): .stack section is too small for allocating stacks for all the harts.
Consider changing `_max_hart_id` or `_hart_stack_size`.");
ASSERT(SIZEOF(.got) == 0, "
.got section detected in the input files. Dynamic relocations are not
supported. If you are linking to C code compiled using the `gcc` crate
then modify your build script to compile the C code _without_ the
-fPIC flag. See the documentation of the `gcc::Config.fpic` method for
details.");
/* Do not exceed this mark in the error messages above | */

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/// PCF8574 -> LCD control pin: Register Select.
pub const PIN_RS: u8 = 0x01;
/// PCF8574 -> LCD control pin: Read/Write.
pub const PIN_RW: u8 = 0x02;
/// PCF8574 -> LCD control pin: Enable.
pub const PIN_EN: u8 = 0x04;
/// Build a PCF8574 output byte for a 4-bit LCD nibble.
pub fn build_nibble(nibble: u8, nibble_shift: u8, mode: u8, backlight_mask: u8) -> u8 {
let mut data = (nibble & 0x0F) << nibble_shift;
if mode != 0 { data |= PIN_RS; }
data |= backlight_mask;
data
}
/// Build the PCF8574 byte with EN asserted.
pub fn nibble_with_en(nibble_byte: u8) -> u8 {
nibble_byte | PIN_EN
}
/// Build the PCF8574 byte with EN de-asserted.
pub fn nibble_without_en(nibble_byte: u8) -> u8 {
nibble_byte & !PIN_EN
}
/// HD44780 row-offset lookup.
const ROW_OFFSETS: [u8; 2] = [0x00, 0x40];
/// Compute the DDRAM address byte for `lcd_set_cursor`.
pub fn cursor_address(line: u8, position: u8) -> u8 {
let row = if line > 1 { 1 } else { line as usize };
0x80 | (position + ROW_OFFSETS[row])
}
/// Format a counter value as `"Count: NNNNNN"` (right-justified, 6 digits).
pub fn format_counter(buf: &mut [u8], count: u32) -> usize {
let prefix = b"Count: ";
buf[..7].copy_from_slice(prefix);
let mut pos = 7;
let digits = [
((count / 100000) % 10) as u8,
((count / 10000) % 10) as u8,
((count / 1000) % 10) as u8,
((count / 100) % 10) as u8,
((count / 10) % 10) as u8,
(count % 10) as u8,
];
let mut leading = true;
for (i, &d) in digits.iter().enumerate() {
if i == 5 || d != 0 { leading = false; }
buf[pos] = if leading { b' ' } else { b'0' + d };
pos += 1;
}
pos
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn build_nibble_command_mode() {
let b = build_nibble(0x03, 4, 0, 0x08);
assert_eq!(b, 0x38);
}
#[test]
fn build_nibble_data_mode() {
let b = build_nibble(0x04, 4, 1, 0x08);
assert_eq!(b, 0x49);
}
#[test]
fn build_nibble_no_backlight() {
let b = build_nibble(0x0F, 4, 0, 0x00);
assert_eq!(b, 0xF0);
}
#[test]
fn nibble_with_en_sets_bit() {
assert_eq!(nibble_with_en(0x38), 0x3C);
}
#[test]
fn nibble_without_en_clears_bit() {
assert_eq!(nibble_without_en(0x3C), 0x38);
}
#[test]
fn cursor_address_line0_col0() {
assert_eq!(cursor_address(0, 0), 0x80);
}
#[test]
fn cursor_address_line1_col0() {
assert_eq!(cursor_address(1, 0), 0xC0);
}
#[test]
fn cursor_address_line0_col5() {
assert_eq!(cursor_address(0, 5), 0x85);
}
#[test]
fn cursor_address_line1_col15() {
assert_eq!(cursor_address(1, 15), 0xCF);
}
#[test]
fn cursor_address_clamps_line() {
assert_eq!(cursor_address(5, 0), 0xC0);
}
#[test]
fn format_counter_zero() {
let mut buf = [0u8; 16];
let n = format_counter(&mut buf, 0);
assert_eq!(&buf[..n], b"Count: 0");
}
#[test]
fn format_counter_one() {
let mut buf = [0u8; 16];
let n = format_counter(&mut buf, 1);
assert_eq!(&buf[..n], b"Count: 1");
}
#[test]
fn format_counter_large() {
let mut buf = [0u8; 16];
let n = format_counter(&mut buf, 123456);
assert_eq!(&buf[..n], b"Count: 123456");
}
#[test]
fn format_counter_six_digits() {
let mut buf = [0u8; 16];
let n = format_counter(&mut buf, 999999);
assert_eq!(&buf[..n], b"Count: 999999");
}
}

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drivers/0x08_lcd1602_rust/src/lib.rs Normal file
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#![no_std]
pub mod lcd1602;

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//! @file main.rs
//! @brief HD44780 16x2 LCD (PCF8574 I2C backpack) demonstration
//! @author Kevin Thomas
//! @date 2025
//!
//! MIT License
//!
//! Copyright (c) 2025 Kevin Thomas
//!
//! Permission is hereby granted, free of charge, to any person obtaining a copy
//! of this software and associated documentation files (the "Software"), to deal
//! in the Software without restriction, including without limitation the rights
//! to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//! copies of the Software, and to permit persons to whom the Software is
//! furnished to do so, subject to the following conditions:
//!
//! The above copyright notice and this permission notice shall be included in
//! all copies or substantial portions of the Software.
//!
//! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//! IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//! FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//! AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//! LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//! OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
//! SOFTWARE.
//!
//! -----------------------------------------------------------------------------
//!
//! Demonstrates 16x2 HD44780 LCD connected via a PCF8574 I2C backpack using
//! the lcd1602 driver (lcd1602.rs). Line 0 shows a static title and line 1
//! displays a live up-counter that increments every second. The counter
//! value is also printed over UART for debugging.
//!
//! Wiring:
//! GPIO2 (SDA) -> PCF8574 backpack SDA (4.7 kohm pull-up to 3.3 V)
//! GPIO3 (SCL) -> PCF8574 backpack SCL (4.7 kohm pull-up to 3.3 V)
//! 3.3V or 5V -> PCF8574 backpack VCC
//! GND -> PCF8574 backpack GND
#![no_std]
#![no_main]
#[allow(dead_code)]
mod lcd1602;
use defmt_rtt as _;
#[cfg(target_arch = "riscv32")]
use panic_halt as _;
#[cfg(target_arch = "arm")]
use panic_probe as _;
use embedded_hal::i2c::I2c;
use fugit::RateExtU32;
use hal::entry;
use hal::Clock;
use hal::gpio::{FunctionI2C, FunctionNull, FunctionUart, Pin, PullDown, PullNone, PullUp};
use hal::uart::{DataBits, Enabled, StopBits, UartConfig, UartPeripheral};
#[cfg(rp2350)]
use rp235x_hal as hal;
#[cfg(rp2040)]
use rp2040_hal as hal;
#[unsafe(link_section = ".boot2")]
#[used]
#[cfg(rp2040)]
pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
#[unsafe(link_section = ".start_block")]
#[used]
#[cfg(rp2350)]
pub static IMAGE_DEF: hal::block::ImageDef = hal::block::ImageDef::secure_exe();
const XTAL_FREQ_HZ: u32 = 12_000_000u32;
const UART_BAUD: u32 = 115_200;
const I2C_BAUD: u32 = 100_000;
const LCD_I2C_ADDR: u8 = 0x27;
const NIBBLE_SHIFT: u8 = 4;
const BACKLIGHT_MASK: u8 = 0x08;
const COUNTER_DELAY_MS: u32 = 1_000;
type TxPin = Pin<hal::gpio::bank0::Gpio0, FunctionUart, PullNone>;
type RxPin = Pin<hal::gpio::bank0::Gpio1, FunctionUart, PullNone>;
type TxPinDefault = Pin<hal::gpio::bank0::Gpio0, FunctionNull, PullDown>;
type RxPinDefault = Pin<hal::gpio::bank0::Gpio1, FunctionNull, PullDown>;
type EnabledUart = UartPeripheral<Enabled, hal::pac::UART0, (TxPin, RxPin)>;
/// Initialise system clocks and PLLs from the external 12 MHz crystal.
///
/// # Arguments
///
/// * `xosc` - XOSC peripheral singleton.
/// * `clocks` - CLOCKS peripheral singleton.
/// * `pll_sys` - PLL_SYS peripheral singleton.
/// * `pll_usb` - PLL_USB peripheral singleton.
/// * `resets` - Mutable reference to the RESETS peripheral.
/// * `watchdog` - Mutable reference to the watchdog timer.
///
/// # Returns
///
/// Configured clocks manager.
///
/// # Panics
///
/// Panics if clock initialisation fails.
fn init_clocks(
xosc: hal::pac::XOSC,
clocks: hal::pac::CLOCKS,
pll_sys: hal::pac::PLL_SYS,
pll_usb: hal::pac::PLL_USB,
resets: &mut hal::pac::RESETS,
watchdog: &mut hal::Watchdog,
) -> hal::clocks::ClocksManager {
hal::clocks::init_clocks_and_plls(
XTAL_FREQ_HZ, xosc, clocks, pll_sys, pll_usb, resets, watchdog,
)
.unwrap()
}
/// Unlock the GPIO bank and return the pin set.
///
/// # Arguments
///
/// * `io_bank0` - IO_BANK0 peripheral singleton.
/// * `pads_bank0` - PADS_BANK0 peripheral singleton.
/// * `sio` - SIO peripheral singleton.
/// * `resets` - Mutable reference to the RESETS peripheral.
///
/// # Returns
///
/// GPIO pin set for the entire bank.
fn init_pins(
io_bank0: hal::pac::IO_BANK0,
pads_bank0: hal::pac::PADS_BANK0,
sio: hal::pac::SIO,
resets: &mut hal::pac::RESETS,
) -> hal::gpio::Pins {
let sio = hal::Sio::new(sio);
hal::gpio::Pins::new(io_bank0, pads_bank0, sio.gpio_bank0, resets)
}
/// Initialise UART0 for serial output (stdio equivalent).
///
/// # Arguments
///
/// * `uart0` - PAC UART0 peripheral singleton.
/// * `tx_pin` - GPIO pin to use as UART0 TX (GPIO 0).
/// * `rx_pin` - GPIO pin to use as UART0 RX (GPIO 1).
/// * `resets` - Mutable reference to the RESETS peripheral.
/// * `clocks` - Reference to the initialised clock configuration.
///
/// # Returns
///
/// Enabled UART0 peripheral ready for blocking writes.
///
/// # Panics
///
/// Panics if the HAL cannot achieve the requested baud rate.
fn init_uart(
uart0: hal::pac::UART0,
tx_pin: TxPinDefault,
rx_pin: RxPinDefault,
resets: &mut hal::pac::RESETS,
clocks: &hal::clocks::ClocksManager,
) -> EnabledUart {
let pins = (
tx_pin.reconfigure::<FunctionUart, PullNone>(),
rx_pin.reconfigure::<FunctionUart, PullNone>(),
);
let cfg = UartConfig::new(UART_BAUD.Hz(), DataBits::Eight, None, StopBits::One);
UartPeripheral::new(uart0, pins, resets)
.enable(cfg, clocks.peripheral_clock.freq())
.unwrap()
}
/// Create a blocking delay timer from the ARM SysTick peripheral.
///
/// # Arguments
///
/// * `clocks` - Reference to the initialised clock configuration.
///
/// # Returns
///
/// Blocking delay provider.
///
/// # Panics
///
/// Panics if the cortex-m core peripherals have already been taken.
fn init_delay(clocks: &hal::clocks::ClocksManager) -> cortex_m::delay::Delay {
let core = cortex_m::Peripherals::take().unwrap();
cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().to_Hz())
}
/// Write one raw byte to the PCF8574 expander over I2C.
fn pcf_write_byte(i2c: &mut impl I2c, addr: u8, data: u8) {
let _ = i2c.write(addr, &[data]);
}
/// Toggle EN to latch a nibble into the LCD controller.
fn pcf_pulse_enable(i2c: &mut impl I2c, addr: u8, data: u8, delay: &mut cortex_m::delay::Delay) {
pcf_write_byte(i2c, addr, lcd1602::nibble_with_en(data));
delay.delay_us(1);
pcf_write_byte(i2c, addr, lcd1602::nibble_without_en(data));
delay.delay_us(50);
}
/// Write one 4-bit nibble to the LCD.
fn lcd_write4(i2c: &mut impl I2c, addr: u8, nibble: u8, mode: u8, delay: &mut cortex_m::delay::Delay) {
let data = lcd1602::build_nibble(nibble, NIBBLE_SHIFT, mode, BACKLIGHT_MASK);
pcf_pulse_enable(i2c, addr, data, delay);
}
/// Send one full 8-bit command/data value as two nibbles.
fn lcd_send(i2c: &mut impl I2c, addr: u8, value: u8, mode: u8, delay: &mut cortex_m::delay::Delay) {
lcd_write4(i2c, addr, (value >> 4) & 0x0F, mode, delay);
lcd_write4(i2c, addr, value & 0x0F, mode, delay);
}
/// Execute the HD44780 4-bit mode power-on reset sequence.
fn lcd_hd44780_reset(i2c: &mut impl I2c, addr: u8, delay: &mut cortex_m::delay::Delay) {
lcd_write4(i2c, addr, 0x03, 0, delay);
delay.delay_ms(5);
lcd_write4(i2c, addr, 0x03, 0, delay);
delay.delay_us(150);
lcd_write4(i2c, addr, 0x03, 0, delay);
delay.delay_us(150);
lcd_write4(i2c, addr, 0x02, 0, delay);
delay.delay_us(150);
}
/// Send post-reset configuration commands to the HD44780.
fn lcd_hd44780_configure(i2c: &mut impl I2c, addr: u8, delay: &mut cortex_m::delay::Delay) {
lcd_send(i2c, addr, 0x28, 0, delay);
lcd_send(i2c, addr, 0x0C, 0, delay);
lcd_send(i2c, addr, 0x01, 0, delay);
delay.delay_ms(2);
lcd_send(i2c, addr, 0x06, 0, delay);
}
/// Set the LCD cursor position.
fn lcd_set_cursor(i2c: &mut impl I2c, addr: u8, line: u8, position: u8, delay: &mut cortex_m::delay::Delay) {
lcd_send(i2c, addr, lcd1602::cursor_address(line, position), 0, delay);
}
/// Write a byte slice as character data to the LCD.
fn lcd_puts(i2c: &mut impl I2c, addr: u8, s: &[u8], delay: &mut cortex_m::delay::Delay) {
for &ch in s {
lcd_send(i2c, addr, ch, 1, delay);
}
}
/// Initialize the LCD, display the title, and log over UART.
fn setup_display(
i2c: &mut impl I2c,
uart: &EnabledUart,
delay: &mut cortex_m::delay::Delay,
) {
lcd_hd44780_reset(i2c, LCD_I2C_ADDR, delay);
lcd_hd44780_configure(i2c, LCD_I2C_ADDR, delay);
lcd_set_cursor(i2c, LCD_I2C_ADDR, 0, 0, delay);
lcd_puts(i2c, LCD_I2C_ADDR, b"Reverse Eng.", delay);
uart.write_full_blocking(b"LCD 1602 driver initialized at I2C addr 0x27\r\n");
}
/// Format and display the next counter value on LCD line 1.
fn update_counter(
i2c: &mut impl I2c,
uart: &EnabledUart,
delay: &mut cortex_m::delay::Delay,
count: &mut u32,
) {
let mut buf = [0u8; 16];
let n = lcd1602::format_counter(&mut buf, *count);
*count += 1;
lcd_set_cursor(i2c, LCD_I2C_ADDR, 1, 0, delay);
lcd_puts(i2c, LCD_I2C_ADDR, &buf[..n], delay);
uart.write_full_blocking(&buf[..n]);
uart.write_full_blocking(b"\r\n");
delay.delay_ms(COUNTER_DELAY_MS);
}
/// Application entry point for the LCD 1602 counter demo.
///
/// Initializes the LCD over I2C with a static title on line 0 and
/// continuously increments a counter on line 1 every second.
///
/// # Returns
///
/// Does not return.
#[entry]
fn main() -> ! {
let mut pac = hal::pac::Peripherals::take().unwrap();
let clocks = init_clocks(
pac.XOSC, pac.CLOCKS, pac.PLL_SYS, pac.PLL_USB, &mut pac.RESETS,
&mut hal::Watchdog::new(pac.WATCHDOG),
);
let pins = init_pins(pac.IO_BANK0, pac.PADS_BANK0, pac.SIO, &mut pac.RESETS);
let uart = init_uart(pac.UART0, pins.gpio0, pins.gpio1, &mut pac.RESETS, &clocks);
let mut delay = init_delay(&clocks);
let sda_pin = pins.gpio2.reconfigure::<FunctionI2C, PullUp>();
let scl_pin = pins.gpio3.reconfigure::<FunctionI2C, PullUp>();
let mut i2c = hal::I2C::i2c1(
pac.I2C1, sda_pin, scl_pin, I2C_BAUD.Hz(),
&mut pac.RESETS, clocks.system_clock.freq(),
);
setup_display(&mut i2c, &uart, &mut delay);
let mut count: u32 = 0;
loop {
update_counter(&mut i2c, &uart, &mut delay, &mut count);
}
}
#[unsafe(link_section = ".bi_entries")]
#[used]
pub static PICOTOOL_ENTRIES: [hal::binary_info::EntryAddr; 5] = [
hal::binary_info::rp_cargo_bin_name!(),
hal::binary_info::rp_cargo_version!(),
hal::binary_info::rp_program_description!(c"LCD 1602 Counter Demo"),
hal::binary_info::rp_cargo_homepage_url!(),
hal::binary_info::rp_program_build_attribute!(),
];
// End of file