DBCS OS/2 System Structure

DBCS OS/2 was developed from version 1.0 and was enhanced in several release in the past. The DBCS OS/2 system structure from DBCS function view point has not been changed but it has grown to support more and more application programs for DBCS/NLS versions of DOS and windows system.

In this section, the OS/2 J is used, as a typical DBCS OS/2 NLV, to show you the common system structure of the DBCS OS/2.

From version 2.0 OS/2 J provides several application program environments like in SBCS OS/2. The DOS and windows application programs for PC DOS, DOS J, DOS J/V can run on the DBCS MVDM and DBCS full screen or seamless Windows systems. The OS/2 full screen or PM application can run on different code page environments that the DBCS OS/2 supports. The DBCS OS/2 supports two code pages (combined code pages), one as the primary and the other is secondary. The code page can be changed by using the CHCP.EXE or the application program interface. The DBCS OS/2 (Japanese version) System Structure shows the system structure of OS/2 J2.1. Please refer the System Structure of Each DBCS OS/2 NLVs for the information of other DBCS OS/2 NLVs.

   ┌──────┐   ┌───────┐    ┌───────────┐   ┌────────────┐   ┌────────────┐
  ┌──────┐│  ┌───────┐│   ┌───────────┐│  ┌────────────┐│  ┌────────────┐│
 ┌──────┐││ ┌───────┐││  ┌───────────┐││ ┌────────────┐││ ┌────────────┐││
 │ DOS  │││ │Windows│││  │Windowable │││ │ (NON─PM)   │││ │  P M       │││
 │ App's││┘ │ App's ││┘  │Application││┘ │Full screen ││┘ │Applications││┘
 │      │┘  │       │┘   │           │┘  │Applications│┘  │            │┘
 └──────┘   └───────┘    └───────────┘   └────────────┘   └────────────┘
    │││         ││          │     │         │      │         │     │  Dynamic
    │││     ====││==========│=====│=========│======│=========│=====│= Link
    │││         ││          │     │         │      │         │     │  Interface
    │││         ││          │ *┌────────────────┐  │         │ *┌────────────┐
    │││         ││          │  │Keyboard/Video/ │  │         │  │Presentation│
    │││         ││          │  │Mouse Subsystem │  │         │  │ Manager    │
    │││         ││          │  └────────────────┘  │         │  └────────────┘
    │││         ││          │          │           │         │      │
 ┌───────────────────────┬───────────────────────────────────────────────────┐
 │ PC─DOS │ Windows 3.x  │ Country Code and Code Page Support                │
 │*DOS J/V│*Windows J3.x │  *Country Code        : 81                        │
 │*DOS J  │              │  *Primary Code Page   : 932 or 942                │
 ├────────┴──────────────┤  *Secondary Code Page : 932 or 942 or 437 or 850  │
 │ M V D M               │                                                   │
 │ Multiple Virtual DOS  │              O S / 2 Kernel                       │
 │ Machine Support       │                                                   │
 └───────────────────────┴───────────────────────────────────────────────────┘
 ┌───────────────────────────────────────────────────────────────────────────┐
 │ * Personal System Device Drivers                                          │
 └───────────────────────────────────────────────────────────────────────────┘

Note :  

  1 .
 The   module   marked   by   an   *   has   code   or   part   of   code   unique   or   modified
from   the   SBCS   OS / 2 .

  2 .
 There   are   two   versions   of   DOS   for   DBCS   countries .    One   exploits   PS / 55
unique   video   system   ( We   call   it   DOS   J , H , T ) ,   and   one   runs   on   any   AT   compatible
machines   which   has   VGA   ( we   call   it   DOS   Jx . x / V ,   Hx . x / V ,   Tx . x / V ) .

DBCS   OS / 2   ( Japanese   version )   System   Structure