Compatibility with the original:
I use now some functionalities of Megas (2 serial ports, I2C interface, analog inputs, digital inputs and outputs). The replica of SainSmart is in everything I've tried compatible with the original and is functioning properly.
From ATmega, the manufacturer of the microcontroller can also be found a Data Sheet for ATmega2560, which is easy to find on the Internet. Usually you do not have the read but, as the important information is available on the website Arduino.cc.
Little attention from Arduino, digitalWrite
The major functions of the Arduino is described super in its website and it developed gradually its possibilities. Only on one point I would like to point here because it is not obvious and one late stumble over it:
The Arduino (also the Mega) has some digital inputs and outputs. When programming it indicates whether they are to be used as input or output. The analog pins but are only inputs. There is no analog outputs, for example, you would have to buy the Arduino Due. For the inputs receives a function "Analog Read". There is also the function "Analog Write", but the controls only some digital outputs with a pulse width modeling. With a properly designed resistor and a capacitor can be from something "analog" but make for a good result is not enough that. There is only sensible solutions through resistance decades in many digital outputs.
Tip:
If you want (music / voice, ...) produce eg tones, you should have a right analog output have (DAC) and the better buy due.
Reasons for the Mega (and not the simple Uno):
Actually, you only need it if you connect really a lot of things and / or needs more memory or speed.
The "normal" Arduino (Uno) has only one serial port, whom you already connects to PC via USB is no longer free. (The lead-out pins of the serial interface are connected in parallel to the serial port used via USB.) This "shortage" but one can very well through the Library "Software Serial" compensate if the resulting interrupts disrupt any other parallel applications. As more and more applications come to wirds then stop close and the Mega offers additional possibilities.
"My" Mega I use as headquarters for a home automation. He communicates in the meantime two UART (transmitter, receiver) of ELV with FS20 components and a weather station, relay controls via the digital outputs for switching different appliances, communicates via I2C with Arduino-Minis, which then control for example lighting, temperature, humidity and measure light and return to Mega. He checked on a keep alive the connected PC and turns it off and on again when the Kepp-Alive fails.
The communication I have solved on the PC with the Haussteurungssoftware IPSymcon with which one can easily organize the communication to the Arduino eingermassen.
The advantage of the Arduino: limited you will still have to lay cables in the house only by your imagination or the opportunity. But also radio items you get for the Arduino ...
Conclusion:
If you can program and likes to tinker the Arduino and its replicas are a really great base. There are so many small program examples that one after just one hour, the first sense of achievement has (software is installed, an LED flash, a voltage is measured).
For more complicated things are so many solutions on the Web to find that you can almost always find help somewhere.
I admit, I am thrilled :-)
Greeting Mangars
