The Rockwell AIM-65 computer was a development computer

Microprocessor development board

A microprocessor development board is a printed circuit board containing a microprocessor and the minimal support logic needed for an engineer to become acquainted with the microprocessor on the board, and to learn to program it...

 based on the MOS Technology 6502

MOS Technology 6502

The MOS Technology 6502 is an 8-bit microprocessor that was designed by Chuck Peddle and Bill Mensch for MOS Technology in 1975. When it was introduced, it was the least expensive full-featured microprocessor on the market by a considerable margin, costing less than one-sixth the price of...

 microprocessor introduced in 1976. The AIM-65 was essentially an expanded KIM-1

KIM-1

The KIM-1, short for Keyboard Input Monitor, was a small 6502-based single-board computer developed and produced by MOS Technology, Inc. and launched in 1976...

 computer. Available software included a monitor with line at a time assembler/disassembler, BASIC interpreter, assembler

Assembly language

An assembly language is a low-level programming language for computers, microprocessors, microcontrollers, and other programmable devices. It implements a symbolic representation of the machine codes and other constants needed to program a given CPU architecture...

, Pascal, PL/65, and FORTH development system. Available hardware included a floppy disk

Floppy disk

A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...

 controller and a backplane for expansion.

Features

Standard software included the system console monitor software in ROM, called Advanced Interactive Monitor. It featured line assembler, disassembler, setting and viewing memory and registers, starting execution of other programs and more. Single stepping was made possible using non-maskable interrupt

Non-Maskable interrupt

A non-maskable interrupt is a computer processor interrupt that cannot be ignored by standard interrupt masking techniques in the system. It is typically used to signal attention for non-recoverable hardware errors...

 (NMI). The command prompt was the less-than sign "<", and on receiving a single character command, it added this input character and the greater-than sign ">". If the thermal printer was turned on, this would be output on a single line. The monitor included a number of service routines that could be accessed and used by a user's program to control I/O and code execution, and was fully documented, including source code.

The machine featured dual cassette tape control. This made it possible to write large assembly programs using the two pass assembler ROM. Source code in text was written twice consecutively to the input tape, and then the assembler, which could start/stop the input cassette tape using motor control was invoked. During the first pass the symbol table was built and stored in RAM. During the second pass symbols would be translated and code written out to the second tape, also using start/stop motor control. Being able to avoid storing code in RAM made it possible to save much space. It was however, still important to keep the symbols list short since RAM size was often no more than 4 KB

Kilobyte

The kilobyte is a multiple of the unit byte for digital information. Although the prefix kilo- means 1000, the term kilobyte and symbol KB have historically been used to refer to either 1024 bytes or 1000 bytes, dependent upon context, in the fields of computer science and information...

.

In 1981 Rockwell introduced an improved model with a 40 character display as the AIM-65/40. An industrial chassis version was known as the System 65 and included a PROM burner and floppy drives. Rockwell was also a pioneer in solid-state storage devices, introducing "bubble memory" non-volatile expansion boards about 1980.

MTU made a "Visible Memory" card in 1978 that worked with the KIM-1 and AIM-65 computers, providing raster graphics

Raster graphics

In computer graphics, a raster graphics image, or bitmap, is a data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium...

 display capability. MTU also made the first real time music synthesizer for a microcomputer; it worked with the KIM-1 and AIM-65, and featured a DAC with software providing 4 voices of wavetable synthesis

Wavetable synthesis

Wavetable synthesis is used in certain digital music synthesizers to implement a restricted form of real-time additive synthesis. The technique was first developed by Wolfgang Palm of PPG in the late 1970s and published in 1979, and has since been used as the primary synthesis method in...

.

In Spain they were distributed by Comelta. This company made various card expansions:

• CR-106 8 Kbytes of RAM
• CR-119 RAM / ROM / PROM expansion
• CR-120 Universal programming
• CR-115 Microcassette controller(two units)
• CR-113 Video controller
• CR-401 Board Bus Extension(Standard S-64)

Comelta assembled all the options in a single box to produce a new computer, the Comelta Drac-1. The first prototype used microcassetes, but definitive versions have two 8" floppy disk drives.

In the late '70s, the Rockwell AIM-65, and successor System 65 became the first computers used onboard a float in the Tournament of Roses Parade. Cal Poly Universities wrote their own animation control language to control hydraulic and motor actuators on floats for many years. In 2003, some of these 27 year old computers were still in use controlling various displays and creatures at a high tech Halloween show near Alexandria, Virginia, U.S.A.

Technical specifications

• Built in full sized QWERTY
  QWERTY
  QWERTY is the most common modern-day keyboard layout. The name comes from the first six letters appearing in the topleft letter row of the keyboard, read left to right: Q-W-E-R-T-Y. The QWERTY design is based on a layout created for the Sholes and Glidden typewriter and sold to Remington in the...
  
   keyboard
• 20 character alphanumeric LED display (16 segments)
• Integrated 20 character thermal printer
• RS-232 serial interface
• Expansion connector
• Application connector with 6522 VIA
  MOS Technology 6522
  The 6522 Versatile Interface Adapter was an integrated circuit made by MOS Technology, as well as second sources including Rockwell and Synertek. It served as a I/O port controller for the 6502 family of microprocessors, providing the parallel I/O capabilities of the PIA as well as timers and a...
  
   chip
• 4 KB RAM
• 5 sockets for 4 KB ROM
  Read-only memory
  Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
  
  /EPROM
  EPROM
  An EPROM , or erasable programmable read only memory, is a type of memory chip that retains its data when its power supply is switched off. In other words, it is non-volatile. It is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages...
  
   chips

Programming

PL/65 was a programming language

Programming language

A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....

 designed and implemented by Rockwell International for the AIM-65.
It is based on a mix of ALGOL

ALGOL

ALGOL is a family of imperative computer programming languages originally developed in the mid 1950s which greatly influenced many other languages and became the de facto way algorithms were described in textbooks and academic works for almost the next 30 years...

 and PL/I

PL/I

PL/I is a procedural, imperative computer programming language designed for scientific, engineering, business and systems programming applications...

, simplified where possible in order to adapt to the limited processing environment afforded by the 6502 (64k memory for instance).

External links

• http://www.oldcomputers.net/AIM-65.html
• AIM-65 at Old Computer Museum
• http://www.obsoletecomputermuseum.org/aim65/
• http://www.old-computers.com/museum/computer.asp?st=1&c=58