The main parts of the control panel: Disc processor The disc CPU is located on two cards. It has a RAM of 64 kilobyte and a ROM of 6 kilobyte. The interface allows the chaining of four disc drive / 8 logical units / and the implementation of a higher capacity / 50 Megabyte / disk as well. The shared printer connector for several parallel interfaces is also located on the CPU disk. CPU: Each control terminal has a CPU, operated by a microprocessor. The memory output is basically the same as the output on the CPU disk. Each CPU contains a serial asynchronous interface to which the display workstations can be connected. Peripherals: Magnetic disk storages: Removable disk /2–2,5 Mbyte/ Display workstations: VDN 52500 display. Software: The functions of the VT-20/IV software system are distributed between the hardware units. The shared resource management tools are running on a CPU disk: a sequential and an index sequential file manager, and the printer SPOOL. All control terminals have a separate operating system which are using the shared resources on the disk CPU. The user applications or the high-level programming languages can be loaded to the operating system of each work respectively.