Product/Service

pmDOS Application

Source: Micro Digital, Inc.
pmDOS has been developed for embedded applications, which have outgrown the limitations of DOS
Micro Digital, Inc. has announced pmDOS, a replacement for DOS and DOS extenders. pmDOS has been developed for embedded applications, which have outgrown the limitations of DOS. It allows smooth migration to 16-bit protected mode. pmDOS offers the following significant advantages over DOS:
  • Huge address space
  • No royalties
  • Segment protection
  • Multitasking
pmDOS is built from the following standard Micro Digital products, which are field-proven and used in hundreds of applications:
  • pmEasy16 16-bit protected mode environment and loader.
  • smx16 real-time multitasking kernel for 16-bit protected mode.
  • unDOS protected mode DOS emulator.
  • smxFile DOS-compatible file manager with floppy and IDE drivers
pmEasy16 is a real-mode .exe file, which can bootload, using the target BIOS, switch the processor to protected mode, then load the application file. This file is a 16-bit protected mode .exe file. The unDOS, smx, and smxFile libraries are linked with the application code. unDOS emulates DOS, in protected mode, without switching to real mode, as DOS extenders do. This guarantees low interrupt latency and hard real-time performance. smx provides a multitasking environment for the application to grow into. smxFile provides DOS file i/o in protected mode.

pmDOS works with the same Borland and Microsoft 16-bit compiler, assembler, and linker that are used for real mode. It is necessary only to set two switches to produce 16-bit protected mode executables. The U.S. Software Soft-Scope debugger is included. It allows debugging .exe application files remotely on the target.

A side advantage of using pmDOS is that 16-bit protected mode really works to increase protection and to find elusive bugs. Each segment is protected from all other segments. An application that seems to work fine in real mode is very likely to experience gpf's (general protection faults) when run in 16-bit protected mode. These gpf's are usually traceable to real bugs, which have been causing occasional hiccups in the real mode version of the system!

Micro Digital, Inc. , 2900 Bristol, G204, Costa Mesa, CA 92626. Tel: 714-437-7333; Fax: 714-432-0490.