LinuxWorks Labs Audio Page


Some of my Arduino-related audio and other electronics projects:

LCDuino-1

An arduino-compatible i2c LCD backpack (libs and sample application can be found here).

Features:

  • "Backpack" board: Plug-in for industry-standard Hitachi-protocol 2x16 LCD modules
  • Atmel ATMEGA328P microcontroller onboard
  • Arduino-compatible (socketed, so user can upgrade controller chips as the become available)
  • Microchip MCP23008 I/O port expander onboard
  • I²C serial control interface
  • Additional analog & digital I/O lines
  • Optional onboard DS1302 real-time clock with its own crystal and supercap backup
  • LCD contrast adjustment trimpot
  • Reset pushbutton switch onboard
  • Power and pin 13 LEDs onboard
  • 5V DC power, user-supplied, for module's input
  • Open-source, user-extensible firmware (add your own new features!)
  • Uses standard FTDI download USB cable support (not included)
  • Central platform for a series of future "application" or "personality " modules, including:
    • Audio preamplifier functions
    • Volume control
    • Analog & digital input/output routing and selection
    • Infrared remote control
    • Camera intervalometer (time-lapse exposure shutter/focus control)
    • Coffee/Espresso machine PID temperature control
    • Other possible uses where a nicely integrated IR remote control input, LCD display (and optional realtime clock) are needed
  • 2-layer PCB with double ground planes
  • Prototype through-plated pads area on 0.1" grid for custom applications
  • Small form-factor: same outline as 2x16 LCD module

The LCDuino-1 is a joint project between AMB Laboratories and LinuxWorks Labs. It is currently under development.


SPDIFmaster

An arduino-controlled SPDIF digital audio input selector (switch).

Features:

  • Digital audio SPDIF switch
  • Controller is the LCDuino-1
  • Supports both coaxial and optical media types
  • Chip supports maximum of 8 ports (5 provided for on the PC board)
  • Onboard support for 1 RCA coax-in port; air-wire support for 2nd coax-in port
  • 1 Toslink output (Toshiba footprint only)
  • All coax ports are Pulse transformer isolated
  • User-defined (short and long) names for each port, displayed on the LCD screen
  • PC board is designed to fit inside a standard hammond enclosure
  • Vishay IR receiver module is the sole method of remote control
  • Switch 'fabric' chip is CD4051
  • Coax input driver chip is uA9637
  • Toslink input blocks support both Toshiba and Sharp footprints
  • 5v DC wall-wart provides power
  • Utilizes a learning IR receiver (currently, Sony IR; more to be added)
  • Fine control over backlight (digitally controlled), including configurable auto-fade (timeout) and total 'lights out' mode

DACmaster

A DAC user interface based on the LCDuino backpack.

Features:

  • This is just one example application, using a AMB Labs Gamma2 DAC
  • Firmware (source code) is general purpose and customizable to the feature set of the DAC being managed
  • Controls a hardware-configurable (ie, non-software mode) DAC such as the AMB Labs Gamma2 DAC
  • Controller is the LCDuino-1
  • Anti-clipping enable/disable selection
  • Filter A/B/C selection
  • Input port (SPDIF) selection
  • Optional interface (software and hardware) to Burr Brown PGA volume control chip
  • User-defined (short and long) names for each port, displayed on the LCD screen
  • PC board is designed to fit inside a standard hammond enclosure
  • Vishay IR receiver module is the sole method of remote control
  • Utilizes a learning IR receiver (currently, Sony IR; more to be added)
  • Fine control over backlight (digitally controlled), including configurable auto-fade (timeout) and total 'lights out' mode

ESPRESSOmaster

An espresso machine controller ("PID") application

Features:

  • Controls a Rancilio Silvia (or similar) espresso machine
  • Controller is the LCDuino-1
  • Uses solid state relay (SSR) to PWM control the heating element in the espresso machine
  • Onboard realtime clock and supercap 'battery' backup keep 24hour time
  • Brew mode and Steam/Froth mode
  • Safety auto-timeout on inactivity
  • Scrolling graph shows temperature, scaled for the most useful range
  • Display can be changed at any time between C and F degrees
  • LM35 as digital heating temperature sensor (via analog-in on the Arduino)
  • Vishay IR receiver module is the sole method of remote control
  • Utilizes a learning IR receiver (currently, Sony IR; more to be added)
  • Fine control over backlight (digitally controlled), including configurable auto-fade (timeout) and total 'lights out' mode

MVCmaster

A motorized volume control application

Features:

  • Controls a motorized potentiometer
  • Controller is the LCDuino-1 or a smaller arduino-compatible board (LCD optional)
  • Uses a common and popular solid state H-bridge (L293D) for motor control
  • Supports the VoluMaster(tm) method of dual-speed volume control ("fast-up", "slow-up", "fast-down", "slow-down")
  • Muting accomplished via relay (non-solid state)
  • Input selector logic available (relay-based)
  • Optional support for LCD (basic motor volume control does not need LCD)
  • Vishay IR receiver module is the sole method of remote control
  • Utilizes a learning IR receiver (currently, Sony IR; more to be added)
  • Fine control over optional LCD backlight (digitally controlled), including configurable auto-fade (timeout) and total 'lights out' mode