Posts | Comments

Planet Arduino

Archive for the ‘microSD’ Category

What we like most about [GreatScott’s] project videos is that he not only shows making them but also the calculations for selecting parts and the modifications along the way. This time he’s made a mini spy bug that records up to nine hours of audio.

His first task was to figure out if the ATmega328p’s ADC is suitable for audio sampling, but only after he explains how sampling works by periodically checking the input voltage from the microphone. Checking the datasheet he found that the ADC’s fastest conversion time is 13 microseconds, which works out to a sampling rate of 76.923 kHz. Good enough.

He then walks through why and how he decided to go with a pre-made amplifier circuit built around the MAX9814 IC. Spoiler alert. His electret’s amplifier output voltage was too low, using an off-the-shelf circuit instead of making his own kept things simple, and the circuit has automatic gain control.

At this point, he added the MicroSD card adapter. Why not just transmit the audio over FM as so many others have done with their hacks? Perhaps he’s worried about someone detecting the transmission and finding his bug.

His final optimization involved getting a good battery life. He measured the circuit’s current draw at 20 milliamps. With a 160 mAh battery capacity, that would be 8 hours of recording time. Removing the Arduino Pro Mini’s voltage regulator and two LEDs got the current down to 18 milliamps and a recording time of 9 hours. Better.

Those are the highlights. Enjoy his full walkthrough in the video below.

Dic
24

Pixelduino – The Arduino with an awesome OLED display!

arduino, microSD, OLED Commenti disabilitati su Pixelduino – The Arduino with an awesome OLED display! 

9e0e86e12eab457883a78438de6273fe_large

by Rabid Prototypes @ kickstarter.com:

The Pixelduino is a tiny Arduino-compatible microcontroller with a full color 1.5″ OLED display + MicroSD built-in!

The Pixelduino is an Arduino-compatible microcontroller that features a 1.5″ 128×128 pixel color OLED screen and a MicroSD slot!

There are all sorts of things you can do with a device like this. You can create wearables like a watch, bracelet, pendant, or buckle that displays color images, attach sensors and display data in text or visual form, display debug information, create a graphics user interface, or even make simple retro games.

Pixelduino – The Arduino with an awesome OLED display! - [Link]

Ott
30

Banguino – 8-bit Processing Module

arduino, Banguino, microSD, uart, USB Commenti disabilitati su Banguino – 8-bit Processing Module 

dtx2-4008c_large_1

by dimitech.com:

Banguino brings the most popular hobby and DIY development platform in the world into a single chip DTX module and offers full backwards compatibility with the most used worldwide Arduino board – the model ‘Uno’.

Bonus features include an on-board power supply to generate +5V and +3.3V to the user’s external circuit, a microSD connector and additional 10 configurable digital I/O ports. There are also two software controllable LEDs on board as well as a USB-to-UART bridge. Banguino provides a highly integrated solution for building simple or complex circuits and benefiting from the large variety of already existing Arduino-compatible code.

Banguino – 8-bit Processing Module - [Link]

Set
26

Arduino TFT Color Clock

arduino, clock, microSD, TFT Commenti disabilitati su Arduino TFT Color Clock 

FIBMI6CI0C8XQQD.MEDIUM

by Sound Guy @ instructables.com:

You may be familiar with a website in the UK called Colour Clock (http://thecolourclock.co.uk/) which converts the time into a hex value and then uses that value to update the background color. It’s very hypnotic and once you get used to how it works you can actually tell where you are in the day just by glancing at the screen from across the room.

I had an Arduino Uno R3 and an Adafruit 1.8″ Color TFT Shield w/microSD and Joystick that I was trying to use for another project that kept stalling out. One night just for fun I decided to see if I could recreate the Colour Clock and it only took a couple hours. If you’re familiar with Arduino you could easily swap parts out for a simple TFT breakout board and something tiny like a Beetle and make a very compact unit. You could even wear it as a badge.

Arduino TFT Color Clock - [Link]

Dic
06

The 86Duino Zero Runs Linux on x86

86Duino, 86Duino Zero, arduino, ethernet, i2c, ipc, Linux, microSD, PCIE, RTOS, SPI, Vortex86EX, x86, xISA Commenti disabilitati su The 86Duino Zero Runs Linux on x86 

86Duino_ZERO-45D

DM&P has been producing low-power, x86-based Vortex processors for the embedded market for over ten years. Now in a nod to the Arduino market they have released the 86Duino Zero, a low-cost Arduino Leonardo sized board powered by their latest 300 MHz SoC Vortex86EX Processor.

This is a fully static 32-bit x86 processor board compatible with Windows OS, Linux and most other popular 32-bit RTOS. It integrates a PCIE bus, DDR3, ROM controller, xISA, I2C, SPI, IPC (Internal Peripheral Controllers with DMA and interrupt timer/counter included). The 86Duino Zero’s ports include USB 2.0 host and device coastline ports, a 10/100 Ethernet port and a microSD slot on the bottom of the board. The Zero’s baseboard also provides a 7-12V power jack, a reset button and a PCIe expansion connector.

The Zero supplies 14 digital I/O pins, half of which can provide 32-bit resolution PWM outputs and six 11-bit analog input pins. Each standard I/O pin supplies 16 mA while the 3.3 V pins can supply up to 400 mA. Like the Intel Galileo development board announced several weeks ago the 86Duino Zero marries Intel architecture to the Arduino platform. Its $39 price tag makes it an attractive proposition. [via]

The 86Duino Zero Runs Linux on x86 - [Link]

Nov
21

BO.Duino – ATmega328 Arduino Compatible board

arduino, AT24, ATmega328, atmel, BO.Duino, clock, DHT11, DS18B20, LED, microSD, Real-time clock, RGB Commenti disabilitati su BO.Duino – ATmega328 Arduino Compatible board 

handmade_pcb

BO.Duino is an Arduino compatible board based on ATmega328 ATMEL’s mcu. This board features many peripherals usually externally connected on a breadboard or prototyping board such as sensors, SD card etc. Peripherals included are:

- A real-time clock
- AT24 series external memory chip
- MicroSD card adaptor (SPI)
- RGB LED
- A potentiometer on analog input
- Connector for DS18b20 or DHt11 series sensors

BO.Duino – ATmega328 Arduino Compatible board - [Link]

Ago
03

Your Image on an Arduino! – TFT LCD Screen Guide

arduino, LCD, microSD, TFT Commenti disabilitati su Your Image on an Arduino! – TFT LCD Screen Guide 

FMVEW3VHHS9LCUC.LARGE

Qtechknow @ instructables.com

Have you ever heard of TFT LCD screens? They are great ways to display information from your Arduino, or display pictures. The Arduino team just released an official TFT LCD screen with their new Robot at Maker Faire 2013. It’s very easy to get started with!! This tutorial will show you how to get the LCD up and running, load information from the SD card, and make a few simple projects.

The TFT LCD screen is a great way to detach your computer, and have the Arduino relay information that you need to know onto the LCD. A great part of the LCD is that it has a built in microSD card socket. You can store images on the microSD card socket, and even some text!

Your Image on an Arduino! – TFT LCD Screen Guide - [Link]

Dic
11

Arduino DMX shield for Christmas projects

arduino, DMX, microSD Commenti disabilitati su Arduino DMX shield for Christmas projects 

This shield allows to connect an Arduino with DMX equipment. It implements the RS485 interface to adapt the electrical levels needed for DMX connection. This shield has been designed with flexibility in mind and allows the user to choose between several Arduino pins for digital input and output of DMX data, it supports a microSD slot and also has the serial connection to support a serial LCD display. We also suggest to use Vixen (www.vixenlights.com) to create sequences on a PC, synced with music, that are sent to Arduino over the serial port.

Arduino DMX shield for Christmas projects - [Link]

Giu
01

Part review – microSD card Arduino shield

arduino, arduino shield, DEV-09802, microSD, microSD shield, part review, shield, sparkfun, tronixstuff Commenti disabilitati su Part review – microSD card Arduino shield 

Hello readers

Today we are going to look at a micro SD card Arduino shield. The reason to use such a thing is to have a storage dump for any data that you generate with your Arduino project that can accept a very large amount of data – up to several gigabytes if you have a large enough micro SD card. With the appropriate sketch it is also possible to read from the card, navigate file directories and so on, but to keep it simple I am just going to examine the most popular aspect – writing our data to the card. However if enough people ask me I will spend the time to figure out the rest.

Initially I imagined this project would be quite difficult, but after some research it was fine. You’re lucky to not have to do the work completed by myself :)

Anyhow, moving on. The shield is shipped in the usual minimalist packaging, a plastic bag and the shield:

You will need to supply your own header sockets or pins and fit them  yourself. I have found the easiest way to do this is to put the pins in the header sockets, as such:

then push these into a solderless breadboard, with the shield on top upside down:

Then solder away. Before you know it, your shield is complete:

The red board colour is a nice contrast with the blue of my TwentyTen. Now of course you will need a micro SD card to write your data to. Contrary to popular belief you can use SDHC micro SD cards that are larger than two gigabytes in size. First of all, you will need to format your micro SD card. Check the instructions or help system of your computer’s operating system to determine how to do this. However ensure that the format type is either FAT32 or FAT 16, not MacOS or ext3 or NTFS, etc.

Next we need to prepare the Arduino IDE to work with the shield. There is a library of functions that needs to be installed for the project to work. Bill Greman has written an excellent library to use, download it from here. After downloading the library, it needs to be installed into the appropriate directory on your computer’s hard drive. If you are unsure how to do this, please read this tutorial by ladyada. If you use Ubuntu like me, place the extracted folder into /usr/share/arduino/libraries

On the software side of things, please note that the shield requires exclusive use of digital pins 10, 11, 12 and 13 for the SPI interface to the card reader.

The next thing to do is test our new shield. Plug the shield into your Arduino Duemilanove or compatible board, then the micro SD card into the slot. It will need a small amount of pressure, as it “clicks” in. Also note that in order to remove the card, you push it and it pops out a little. Don’t try to just pull it out with your thumbnail. It is also wise to only insert and remove the card when the power is off.

Assuming you have installed your library correctly, fire up the Arduino IDE and select File menu > examples > SDFat > SDFatinfo. Plug in your shield, upload the sketch, then hit the serial monitor button. Enter a character and press enter – you should be presented with something like:

This display shows various data about the card, the formatting type and so on. If it did not work, check your soldering on the shield, re-format the card with FAT16 or FAT32, reseat the shield into the Arduino, reconnect to the PC and try again.

Next it is time to write something to the card, to get a feel for how things work. Run the “SDFatwrite” example, open the serial monitor box, enter a character and press enter. Now open the resulting text file found on your micro SD on your computer. You should have something that looks like:

There really is a lot of code in the demonstration sketch, but to make things easier to adapt, have a look at line 90 to 94 of the sketch.

The writeString() function writes text to the file, just like Serial.write() would to the screen. The writeNumber() function writes integers, or unsigned integers to the file. And the writeCRLF() function starts a new line in the file. You can basically copy and paste the code into your own sketch and use these functions, as long as your variable types are suitable for the functions.

In saying that, I have made a demonstration sketch to prove this. Using the real time clock shield from last week’s articles, an Analog Devices TMP36, and a 560 ohm resistor/LED on digital pin 2, we can make a temperature logger with time and date. This involves a nice stack of Arduino goodness:

and a solderless breadboard with the temperature sensor and the LED setup. If you had a really small breadboard, you could plonk it into the micro SD shield and save space. Alas, mine did not fit.

But it worked. Now for the sketch – you can download it here: demonstationsketch.pdf. If you examine the sketch I have filled it with comments and points of interest. If you are unsure of how the real time clock code works, please visit here. Fore more information about the temperature sensor, please visit here. There was no need to compute Fahnrenheit in the sketch, as this can be done later on in a spreadsheet, saving you sketch memory and storage space.

The purpose of the LED is to let you know when the sketch is about to start, and when it has finished. Once the blinking starts at the end of the sketch, you can power off and remove the micro SD card as the program has written and closed the file. If you do this before the sketch has finished, you may corrupt the file and lose your data.

Here is an example of the file from the demonstration sketch:

Notice how there are distinct columns between the data. This is important as later you may want to import the text file into a spreadsheet to analyse your data. For example, if you use the Insert > Sheet from file… command in the Openoffice.org spreadsheet, you can select which columns of data to import, like this:

Which will leave you with nicely delimited data that you can twist around to your heart’s content:

In this spreadsheet I have calculated the minimum, maximum and average temperature – and in Fahrenheit as well. By just capturing the raw data using the micro SD shield you can offload a lot of processing work from the Arduino and onto your personal computer  - a much more efficient solution. The spreadsheet has been places in the files section of our Google Group.

So there you have it. You now have the tool and an understanding of how to capture data from the real world, and bring it home to analyse and make decisions from it. The possibilities are almost limitless, using a wide range of sensors, user inputs, even GPS modules, you can get a better understanding of the world around you.

The shield is available from the usual range of retailers, and this one was purchased from Little Bird Electronics.

High resolution photos are available on flickr.

As always, thank you for reading and I look forward to your comments and so on. Please subscribe using one of the methods at the top-right of this web page to receive updates on new posts. Or join our new Google Group.

Stay safe and make something!




  • Newsletter

    Sign up for the PlanetArduino Newsletter, which delivers the most popular articles via e-mail to your inbox every week. Just fill in the information below and submit.

  • Like Us on Facebook