Visi On - Technical Information

Technical Information

Visi On worked on IBM PCs that used an Intel 8086 CPU and DOS operating system; it is possible to run Visi On on DOS 6.22, but it requires a special mouse, small partition and an XT computer. Visi On required 512 kilobytes of RAM and a 5 megabyte (or more) hard drive (FAT12 file system only, so maximum partition size must be 15MB). The software ran in CGA 640x200 monochrome graphics mode. It could work with multiple applications at the same time. It had built-in documentation and help files. Visi On required Mouse Systems-compatible mice; Microsoft-compatible PC mice, which over time became the standard, were introduced later (in May 1983).

Visi On used two mouse drivers. First, loaded in text mode, made mouse registers accessible to the embedded driver, which translated coordinates to cursor position. This internal driver, built-in as a subroutine into VISIONXT.EXE, required Mouse Systems PC-Mouse pointing device. It was impossible to work using MS mouse because of protocol differences.

Visi On was targeted toward high-end (expensive) PC workstations. Visi On applications were written in a subset of C VisiC, and a third-party could have ported the core software (VisiHost, VisiMachine virtual machine, VISIONXT.EXE in IBM PC DOS version) to Unix, but that never occurred. In 1984, VisiCorp's assets were sold off to Control Data Corporation.

Making working copies of the original floppy disks using modern methods is difficult - they are protected using pre-created bad sectors and other methods of floppy disk identification. However, Nathan Lineback has made Disk Images available. The legal status of these disk images is unknown.