Hardware Development

This section contains information for hardware developers working on the Latency Recorder project.

Firmware Documentation

The latency recorder firmware is written in Rust and consists of three main components:

Core Library (latreclib)

A #![no_std] library providing helper functions and abstractions for the latency recorder hardware.

Recorder Firmware

The main firmware application that runs on the Arduino hardware. This handles:

• ADC sampling at high frequency
• Serial communication with the host computer
• Timing and synchronization
• Hardware control

Simulator

A hardware simulator that allows testing the firmware logic without physical Arduino hardware.

API Documentation

The firmware is documented using Rust's built-in documentation system. The API documentation includes:

• Bit manipulation functions: bools2num() and num2bools() for converting between boolean arrays and numeric values
• Hardware abstractions: Low-level interfaces for AVR microcontroller
• Usage examples: Comprehensive code examples for all functions

View API Documentation

Generating Documentation

To regenerate the API documentation for the firmware:

./generate-docs.sh

Note: The recorder and simulator documentation requires the AVR toolchain to be properly configured.

Hardware Components

Arduino Nano

• ATmega328P microcontroller
• 16 MHz clock speed
• 10-bit ADC with up to 15 kHz sampling rate
• Serial communication at 115200 baud

Signal Conditioning

• TLV2462 op-amp for signal amplification
• Voltage divider for input protection
• Low-pass filtering for noise reduction

Development Setup

1. Install Rust and required targets:

   rustup target add avr-unknown-gnu-atmega328

2. Install AVR toolchain (macOS):

   brew tap osx-cross/avr
   brew install avr-gcc avrdude

3. Build the firmware:

   cd firmware/recorder
   cargo build --release

4. Flash to Arduino:

   avrdude -p atmega328p -c arduino -P /dev/tty.usbserial-* -b 115200 -U flash:w:target/avr-atmega328p/release/recorder.elf:e