Micros pequeños, para Proyectos pequeños. Más de una vez os habrá pasado, que después de haber testeado vuestro prototipo deseáis hacer de él una aplicación real.
Sin embargo, si es un proyecto pequeño, con pocas salidas/entradas parece poco lógico/óptimo emplear un ATmega328 con sus 14 salidas digitales y sus 6 entradas analógicas, con el consiguiente gasto de dinero y espacio. (La mejor solución es aquella que, cumpliendo su objetivo, sea la más fácil, sencilla y barata...Optimización!). Si estáis familiarizados con el uso de microcontroladores PIC o AVR y tenéis los conocimientos y herramientas (compiladores, grabadores...) necesarios, esto se resuelve fácilmente acudiendo al micro que más se ajusta a nuestras necesidades...y este post no tendría sentido! ;P Vamos a ver cómo podemos programar los micros AVR ATtinny45 y 85 utilizando un Arduino (Uno, Duemillanove...) como grabador por ICSP. Yo me voy a centrar en el Attinny85, aunque todo lo visto aquí puede ser usado con su hermano menor, sin ninguna variación. Audio Amplifiers.
Modest power audio amplifiers for driving small speakers or other light loads can be constructed in a number of ways.
The first choice is usually an integrated circuit designed for the purpose. A typical assortment can be seen on this National Semiconductor page. Discrete designs can also be built with readily available transistors or op-amps and many designs are featured in manufacturers' application notes. Older designs employed audio interstage and output transformers but the cost and size of these parts has made them all but disappear. (Actually, when the power source is a 9 volt battery, a push-pull output stage using a 500 ohm to 8 ohm transformer is more efficient than non-transformer designs when providing 100 milliwatts of audio.) Here are a few easy-to-build audio amplifier circuits for a variety of hobby applications: Simple LM386 Audio Amplifier. Getting Started with Arduino! – Chapter Four. This is part of a series titled “Getting Started with Arduino!”
– A tutorial on the Arduino microcontrollers. The first chapter is here, and the complete index is here. In this chapter will be looking at getting more outputs from less pins, listening to some tunes, saying hooray to arrays, and even build a self-contained data logger. More pins from less – sounds too good to be true, doesn’t it? No, it is true and we can learn how to do this in conjunction with a special little IC, the 74HC595 Serial In/Parallel Out 8-bit Shift Register. Before we get too carried away, we need to understand a little about bits, bytes and binary numbers. A binary number can only uses zeros and ones to represent a value. See how each digit of the binary number can represent a base-10 number. Now each digit in that binary number uses one ‘bit’ of memory, and eight bits make a byte. So if you send the number 255 to the ’595, all of the output pins will go high. Now to the doing part of things. Where: ShiftOut. Learning Examples | Foundations | Hacking | Links Started by Carlyn Maw and Tom Igoe Nov, 06 Shifting Out & the 595 chip At sometime or another you may run out of pins on your Arduino board and need to extend it with shift registers.
This example is based on the 74HC595. The datasheet refers to the 74HC595 as an "8-bit serial-in, serial or parallel-out shift register with output latches; 3-state. " How this all works is through something called "synchronous serial communication," i.e. you can pulse one pin up and down thereby communicating a data byte to the register bit by bit. The "serial output" part of this component comes from its extra pin which can pass the serial information received from the microcontroller out again unchanged.
"3 states" refers to the fact that you can set the output pins as either high, low or "high impedance. " Here is a table explaining the pin-outs adapted from the Phillip's datasheet. Example 1: One Shift Register The Circuit. .NET Micro Framework – More blinking LEDs. Some time ago I wrote about FEZ Mini and FEZ Domino – first affordable development boards for .NET Micro Framework.
Today I’m excited to tell you about another device called Netduino. Similar to FEZ Domino this board is pin compatible with Arduino, and therefore most of Arduino shields should work fine on Netduino. This makes transitioning your project quite easy. Only care should be taken to ensure that shield can run at 3.3V logic levels (because Arduino runs at 5V). Of course Netduino is much more powerful than Arduino, thanks to Atmel 32-bit microcontroller running at 48Mhz, 128KB flash for code, and 60KB of RAM.
You can find few introduction videos at to get you up and running with hardware and software configuration so I won’t repeat it here. Netduino has 14 digital pins, and 6 analog pins that can be used as digital as well. Shift registers are very simple ICs, and one popular chip is 74HC595. Hardware setup Here are the schematics of the circuit. Example 1 – using potentiometer.