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BMS map is a program which is written in Assembly language to manage screens. The three macros that are used to define the screen are DFHMSD, DFHMDI, and DFHMDF.

BMS Macro Coding Sheet

BMS map definitions are purely assembler macros, the following coding convention must me maintained.

1-8 Label
10-15 Macro name
16-71 Operands
72 Continuation
  • Label:

    Label is name of the operation. If the macro is DFHMSD, it specifies map-set name. If the macro is DFHMDF then it specifies field name.

  • Macro name:

    There are three macros used in BMS coding.

    1. DFHMSD - Defining Mapset

    2. DFHMDI - Defining Maps
    3. DFHMDF - Defining Fields

    All the BMS coding starts with DFHMSD followed by one or more DFHMDI. One or more DFHMDF follow DFHMDI.

  • Operands:

    Define the parameters for the macro being invoked.

  • Continuation:

    Continuation of macro is achieved by ‘X’ in 72nd column of the current line and continues from the 16th column of next line.

  • Comments:

    Comment lines are indicated by ‘*’ in column 1. A comment line cannot be placed between continuation lines and comment lines cannot be continued.

  • Blank lines:

    You cannot have blank lines in the assembler program.

We will see each Macros in next chapter...

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