Assembler instructions

Figure 5. Ordinary assembler instruction statements
             *---------------*        *---------------*        *---------------*
             |     NAME      |        |   OPERATION   |        |    OPERAND    |
             |     Field     |        |   Field       |        |    Field      |
             *-------*-------*        *-------*-------*        *-------*-------*
                     |                        |                        |
                     V Which                  V Which                  V Which
                     | can be                 | must be                | can be
             *-------*-------*        *-------*-------*        *-------*-------*
             |    A Symbol1  |        |   A symbolic  |        |  Zero or more |
             |   (or space)  |        |   Operation   |        |  operands     |
             |               |        |   Code2       |        |               |
             *---------------*        *---------------*        *-------*-------*
                                                                       |
                                                                       |
                       *-----------------------------------------------*----------------------------*
                       V                                                                            V
            *----------*----------*                                                      *----------*----------*
            | For Data Definition |                                                      | For all other       |
            | (DC and DS          |                                                      | ordinary Assembler  |
            | Instructions)       |                                                      | Instructions        |
            *----------*----------*                                                      *----------*----------*
                       |                                                                            |
                       V Operands can be                                                            V Operands
                       | composed of one                                                            | can be composed
                       | to five subfields3                                                         | of3
      *----------------+--------------*---------------*----------------*            *---------------+----------------*
      |                |              |               |                |            |               |                |
*-----*------*  *------*-----*  *-----*------*  *-----*------*   *-----*------*     |               |                |
|            |  |            |  |            |  |            |   |            |     |               |                |
|Duplication |  |    Type    |  |    Type    |  |  Modifiers |   |   Nominal  |     |               |                |
| factor     |  |            |  |  Extension |  |            |   |    Value   |     |               |                |
|            |  |            |  |            |  |            |   |            |     |               |                |
*------*-----*  *------*-----*  *-----*------*  *-----*------*   *-----*------*     |               |                |
       |               |              |               |                |            V               V                V
       |               |              |               |                |            |               |                |
       V               V              V               V                V      *-----*------*  *-----*------*   *-----*------*
       | *-------------*              |               |                |      | Expression |  | Character  |   |  Symbolic  |
       | |  *-------------------------*               |                |      | (e.g.*+14) |  |   String   |   |   Option   |
       | |  |   *-------------------------------------*                |      |            |  | (e.g. 'XX')|   | (e.g. GEN) |
       | |  |   |     *------*                                         |      *------------*  *------------*   *------------*
       | |  |   |     |      |                                         |
       V V  V   V     V      |                                         V
 e.g. 10 E  B   L2  '12'     |                                         | One or more nominal values
     *--*--*--*---*-----*    |   *------------------------*------------*-------------*--------------------------*
                             ^   |                        |                          |                          |
                             |   V                        V                          V                          V
                         *---*---*-------*        *-------*-------*           *------*------*           *-------*-------*
                         | 'Decimal      |        | (Expression)  |           | 'Character  |           | 'Graphic      |
                         |  number'      |        |               |           |  string'    |           |  string'4     |
                         | (e.g. '12')   |        | (e.g. (ADDR)) |           | (e.g. 'ABC')|           | (e.g. '<.A>') |
                         *---------------*        *---------------*           *-------------*           *---------------*

1 Can be an ordinary symbol, a variable symbol, or a sequence symbol
2 Includes symbolic operation codes of macro definitions
3 Discussed more fully where individual instructions are described
4 With DBCS option only

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