Y6502 is a 6502 simulator which runs on VAX/VMS and originally on the MUSIC operating system for IBM mainframe platforms. Additional code implements a subset of the 6502 based BBC Microcomputer. The BBC Micro operating system is not run natively but sufficient operating system entry points are provided by the simulation to enable language ROM images such as BBC Basic to run natively.
It is possible to read and write files in the VMS filesystem. Keyboard input and most text based screen operations are possible, however, graphics operations, sound and other I/O methods are not provided for. Other than that, an environment similar to that in a 6502 second processor is provided. More 6502 memory is available for programs as less is required for OS functions but attempts to access hardware directly do not work, particularly attempts to access screen memory directly.
Its origins are in a Z80 simulator written in FORTRAN IV to run on the MUSIC operating system for IBM System/370 machines. This was the inspiration for a 6502 simulator to run on the same system, the core of which eventually became IBM/370 assembly language. This was ported to VAX/VMS with the 6502 core becoming VAX MACRO assembly language.
VMS format zip archive containing Y6502 for VAX/VMS
Source files may also be browsed here
Mail _software_@_beyondthepale_._ie_ (without the underscores) for further information.