![]() |
|
Type | development computer |
---|---|
Release date | 1978 |
Introductory price | US$375 |
CPU | MOS Technology 6502 |
Memory | 1K RAM |
The Rockwell AIM-65 computer was a development computer introduced in 1978 based on the MOS Technology 6502 microprocessor. The AIM-65 was essentially an expanded KIM-1 computer. Available software included a line-oriented machine code monitor, BASIC interpreter, assembler, Pascal, PL/65, and FORTH development system. Available hardware included a floppy disk controller and a backplane for expansion.
Rockwell advertised the $375 AIM-65, with 1K RAM, as an "easy, inexpensive [computer] ... for learning, designing, work or just fun". Standard software included the system console monitor software in ROM, called Advanced Interactive Monitor. It featured an assembler, disassembler, setting and viewing memory and registers, starting execution of other programs and more. Single stepping was made possible using non-maskable interrupt (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.