Electronic – Why are some AVRs marked with ‘atmega’ and some marked with ‘mega’

The AVR family has a lot of good, inexpensive, hobbyist-friendly devices with nice peripherals, low power consumption, and good cross-platform support.

Yes, Arduino is a big part of it. But I think that Arduino came to exist the way that it did -- and to the success that it has -- partly due to those features.

• Good: They work well. Easy to program in C for most basic functions. Adequate documentation.

• Inexpensive: Lots of $3-$5 parts, available from major distributors in small quantity.

• Hobbyist friendly: Parts in through-hole packages-- a big contrast to many of the chip families out there today. Newer AVR (e.g., xmega) devices are less so.

• Nice peripherals: Built-in oscillator, flash memory, on-board RAM, serial ports, ADC, EEPROM, and the other goodies that make it possible to run a single MCU on a protoboard to do basic stuff, without too much hassle.

• Low power consumption. AVR's major pitch point these days. Suckers can run on a battery almost forever if you know what you're doing.

• Good cross-platform support: The AVR was designed with C support in mind-- not as an afterthought. GCC support came early, and a big open source community developed around that. It's still one of the best MCUs that you can develop from any platform with free tools. This is a big one with respect to the other families, many of which use proprietary compilers or have lackluster gcc support. Even PIC was pretty late to the game with good free C compilers.

As for why there wasn't much about it in the replies to your earlier question, I think that (1) you're seeing small sample bias and (2) many of the answers were specifically to discuss non-AVR solutions-- because so much of the discussion on this site is AVR/Arduino-centric. Most of the microcontroller families aren't represented in your list as of this writing-- including some that I use regularly, and others that are among the most popular in the world.

AFAIK, there isn't one!