Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Keeping kids entertained with Arduino Mini BMO

First of all what is BMO? Simply speaking it is a living game console plus music player, camera, alarm clock and everything you can think off. Fileark wanted to build something similar to original one so he started an Arduino based BMO. Central brain if it is Arduino Pro Mini with Nokia 3310 LCD screen. He placed all components in to nice custom 3D printed box, that mimics original BMO. Currently it is equipped with WTV020-SD Audio player to play different loaded sounds (amplifier and couple speakers are also included). 2Y0A21 Sharp distance sensor and ADXL335 accelerometer gives some interactivity while playing around. There are 7 push buttons for selecting things and playing games. As you can see this is a platform which can be further expanded with sensors and functions. Eventually you may run out of memory or processing speed. So for project like this probably it is better to start with faster processor or board like Raspberry Pi. You can put lots of stuff in it and then see kids trying to explore its capabilities. Continue reading

Basics on playing WAV with Arduino

Sometimes you may want to ad sound to your projects, but adding additional hardware (like MP3 decoder) doesn’t seem worth efforts and expenses. Beep tones also seem to be not acceptable. What you are left with is simple WAV player, which can be played directly from microcontroller pin using PWM modulation. How hard can it be to set up a simple WAV player on Arduino? Kathy Yang has shared great guide on building simple WAV player on Freaduino UNO. He vent through all steps how to get your results. First of all he goes through audio basics where he analyzes sampling and quantization. This is a point where you need to decide your sound quality. Then follows to getting audio data from WAV files because file consists of data part (head) and audio data that can be played. The rest is to store audio data in to RAM. OF course with limited RAM you can play couple seconds of audio. If you are looking for more space, you can use external storage like SD card, EEPROM, flash, etc. Audio data… Continue reading

Multimeter hacked with talk module

Talking gadgets may be annoying, but sometimes they can be a big helpers. One situation – blind people. Voice messages can help make electronics useable. Another situation is when you can’t look at display due to complex task you are doing or you are in position when you cannot see it. Either way voice on devices might be useful. MastroGippo had a request to convert multimeter into talking one. He found out that there is no many multimeters on market that talks. Some of them are expensive, while other discontinued. Instead of struggling to find one he started hacking. He found that simplest and cheapest way is to play prerecorded sounds with Arduino. He stored number waves in to SD card. Another problem is number pronunciation in different languages. Luckily In Italian it sounds like like “hundreds” + “tens” + “ones”. So converting number to sound is easy. Other languages may struggle a bit (eg. France). After number is captured, an Arduino simple SDAudio library takes care of playing it. As housing he used cheep phone speaker that carries all… Continue reading

Playing wav files with Arduino

Sound functionality can push your design to new level. It may seem that playing recorded sounds with micros like AVR is quite intense, but in reality this is easy. And the only limitation here is memory storage. Husham Samir published his instructable on how to play wav files with Arduino Nano 3.0. His set up uses SD card for storing wav files striped to to 8-bit and 16000Hz sampling. This indeed is enough to get decent quality of voice messages. There are four buttons used that allow selecting one of four files to be played. Player code relies on TRMpcm library which is specially created to play PCM/WAV files directly from SD card. Continue reading

Impressive audio Synthesizer machine driven by Arduino Mega

Tim and Steve have been working on interesting project at high school class. This is called Digital Audio Workstation. This is practically audio synthesizer based on Arduino Mega. It has everything you might need to play various tunes. Tones can be input visually by taping to LED matrix which is placed under resistive touch screen. 2X16 LCD menu displays current position and allows accessing other settings like save, load tune change waveform. Audio is played through Maxim7224 8-bit DAC, which comes with output amplifier. They had to solve many difficulties during process. First of all to make touchpad interpret correct coordintes so LED matrix would match correct inputs. Also they made 768×24 virtual matrix that can be scrolled inside 8×8 LED matrix. So there were no way to put everything in to large array since audio part also took his part. They made smaller matrix which was updated from full matrix on play to preserve RAM. Anyway in 9 moths they made it working and even play Fur Elise. Continue reading

Arduino Sound Synthesis

This is not exactly a project, but a skill builder which talks about how to generate simple to complex sounds with and without using a digital to analog converter. We all know, that to PWM is the best method without any hardware complexity to generate any analog voltage you want. However it might be really tough to program to generate a musical tone that sounds good to ear. A bit banging is the most simplest of sound you can generate by simply connecting the pin to a speaker, and driving the pin high and low continuously. Another method is to use a R2R ladder network for converting digital to analog data and then driving the speaker through its output. However there are chances of noise in this method. Moving further, you will find different listings in the code given, that has codes of creating notes, morphing waveform. It even feature filter capabilities that adds ‘waa’ and ‘yeow’ to the end of the sound by using coefficients of a Low pass filter. The Arduino is Arduino Nano, but if you use… Continue reading