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for Macro Instructian Compiler Assembler

Macro assembler for the SOS system for the IBM 7090

Related languages
MICA => MOBL   Target language for
MICA => SCAT   Target language for

  • Haigh, M "Users specification for MfCA" SHARE distribution 1959 view details
  • Hoffman, Joyce and Opler, Ascher "Use of MOBL in preparing retrieval programs" view details Extract: Description
    Description of the MOBL-MICA System

    MICA is an hierarchically organized compiler with a dominant system macro at the highest level. One level below the system macro lies the users program written in  the form of one macro. This may contain machine coding library macros and user's macros. By sublevel nesting of  macros, the user can eliminate redundant effort in the construction of new macros.

    If an address field is not defined in the macro which references it, the next higher level macro is examined and then the next, until the symbol is found. If the symbol is defined in more than one skeleton, MICA will alter the symbol (and all references to it) at each occurence to provide uniquely defined symbols. Operation codes (macros or machine coding), as well as location symbols, may appear as parameters; This allows MICA to compile alternate operations, depending on the decisions made at compiling time usually based on pr definitions.

    Fields may be defined without concern for word boundaries and may be either alphanumeric or binary. Once specified, the user may reference these fields with little concern for their description. For example, when using the MOVE macro, the user need only provide the symbolic locations (indexable) of the "from" arid "to" fields. The compiler will be responsible for such things as shifting, changing modes, masking and making the necessary  adjustments when the fields are unequal in length.

    The following types of macros are provided by the MOBL library:
    - Input-Output
    - Data Definitions
    - Field Test and Control
    - Arithmetic
    - Logic Control
    - Field Editing
    - Indexing
    - Debugging Extract: Technique
    Technique of Writing With MOBL
    To write a retrieval program in MOBL, one prepares the data description which defines files, records and fields. One then proceeds to write the procedure using, for the most part, the macros provided by the MOBL language which address the files, records and fields previously defined. These describe the required manipulations. A significant feature of an hierarchical macro system like MICA is that it allows simple extensions of the language by creating new procedures (user macros ) to embody repeated actions.

          in [ACM] CACM 4(09) (September 1961) view details