Atmel AVR

The AVR is a modified Harvard architecture 8-bit RISC single-chip microcontroller, which was developed by Atmel in 1996. The AVR was one of the first microcontroller families to use on-chip flash memory for program storage, as opposed to one-time programmable ROM, EPROM, or EEPROM used by other microcontrollers at the time.

Brief history

The AVR architecture was conceived by two students at the Norwegian Institute of Technology (NTH), Alf-Egil Bogen and Vegard Wollan.

The original AVR MCU was developed at a local ASIC house in Trondheim, Norway, called Nordic VLSI at the time, now Nordic Semiconductor, where Bogen and Wollan were working as students. It was known as a μRISC (Micro RISC) and was available as silicon IP/building block from Nordic VLSI. When the technology was sold to Atmel from Nordic VLSI, the internal architecture was further developed by Bogen and Wollan at Atmel Norway, a subsidiary of Atmel. The designers worked closely with compiler writers at IAR Systems to ensure that the instruction set provided for more efficient compilation of high-level languages. Atmel says that the name AVR is not an acronym and does not stand for anything in particular. The creators of the AVR give no definitive answer as to what the term "AVR" stands for. However, it is commonly accepted that AVR stands for Alf (Egil Bogen) and Vegard (Wollan)'s RISC processor. Note that the use of "AVR" in this article generally refers to the 8-bit RISC line of Atmel AVR Microcontrollers.

AVR 661

AVR 661 is an R-1 type United States Air Force "crash boat", a boat used in air-sea rescues. It is 85 feet long and has two Packard Marine 4M-2500 engines of 1500 horse power. It has a top speed of 35 knots. The boat was armed with a twin .50 caliber machine gun, a 20 mm anti-aircraft gun and two depth charges.

These types of boats were used to rescue aircraft crews at sea. The designation AVR was used for "Aircraft Rescue Vessel", so it was one of the small, fast craft, that were used for rescuing pilots from downed planes.

AVR 661 was built in 1943 for the Army Air Corps and served in the Gulf of Mexico during World War II.

After the war the Air Force sold many of its crash boats to private parties for use as yachts or commercial vessels. Many others were used as targets and sunk. AVR 661 was kept in active service assigned to Tyndall Air Force Base, near Panama City, Florida. During the Vietnam War, AVR 661 towed targets for helicopter gunship training and anti-mine training as well as to recover drones.