TX/CLAUDE.md

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

This is an embedded C application for the LPC54114 microcontroller (ARM Cortex-M4) running on the LPCXpresso54114 development board. The project appears to be a transmitter device (TX) with signal generation, display, USB communication, and power management capabilities.

Hardware Target: NXP LPC54114 dual-core Cortex-M4/M0+ microcontroller Software Version: 1.10A (defined in source/System/system.h:18)

Build System

Build Commands

# Build debug version
cd Debug
make all

# Build release version  
cd Release
make all

# Clean build artifacts
make clean

Build Artifacts

• Target executable: TX_App.axf (ARM executable format)
• Binary output: TX_App.bin (generated post-build)
• Memory map: TX_App.map
• Linker scripts: TX_App_Debug.ld, TX_App_Release.ld

Toolchain

• Compiler: arm-none-eabi-gcc
• Target: Cortex-M4 with hardware floating point (fpv4-sp-d16)
• IDE Support: MCUXpresso, IAR, Keil MDK

Code Architecture

Core System Structure

Main Application Flow:

• Entry point: source/main.c
• System initialization: source/System/system.c
• Hardware initialization: source/init.c

Key Subsystems:

1. Signal Generation (source/dds.c, source/fgen.c)

   • DDS (Direct Digital Synthesis) for frequency generation
   • Function generator capabilities
   • Frequency range: 3.14kHz - 200kHz for broadcast mode
   • System clock: 12MHz

2. Display System (source/display.c, source/lcd.c)

   • Graphics library in source/Graphics/
   • Font rendering system in source/Fonts/
   • Multi-language support with translations
   • Icon and bitmap handling

3. Power Management (source/battery.c, source/ports.c)

   • Battery type detection (Lithium/Alkaline/External DC)
   • Power limits: 10W (Lithium/Ext), 5W (Alkaline)
   • Clamp control and regulation

4. Communication (source/USB/, source/broadcast.c)

   • USB CDC (Virtual COM) interface
   • Broadcast transmission capabilities
   • Flash update support via USB

5. Hardware Drivers (source/driver.c, source/io.c)

   • SPI communication for external components
   • ADC for measurements
   • Timer and PWM control
   • GPIO port management

Directory Structure

• source/ - Main application code
• source/System/ - System-level configuration and data structures
• source/USB/ - USB device implementation
• source/Graphics/ - Display graphics and UI
• source/Fonts/ - Font data and localization
• source/Loader/ - Bootloader and flash update functionality
• drivers/ - NXP SDK peripheral drivers
• CMSIS/ - ARM CMSIS headers
• usb/ - USB middleware stack
• Debug/, Release/ - Build output directories

Key Data Structures

ClampData_t (source/System/system.h:35): Core control structure containing:

• Slope, voltage, current, impedance measurements
• Power regulation parameters
• Digital potentiometer settings

Development Notes

• The project uses NXP's MCUXpresso SDK for peripheral drivers
• Hardware-specific fixes are isolated in source/hwFixes.c
• Comprehensive change log maintained in source/AppChangeLog.txt
• Flash memory layout: Application starts at 0x10000 (64KB offset for bootloader)
• Maximum application size: 192KB

Testing

Connect via USB (J7 connector) at 115200 baud for debug console output. The application supports firmware updates through the bootloader system.