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*DECK     SSBTBW
          IDENT  SSBTBW 
          ENTRY  SSBTBW 
          TITLE  SSBTBW - TEST BIT IN WORD. 
*COMMENT  TEST BIT IN WORD. 
 SSBTBW   SPACE  4,10 
***       SSBTBW - TEST BIT IN WORD.
* 
*         S.H. FISCHER.      81/08/17.
          SPACE  4,10 
***       SSBTBW IS A ROUTINE TO EFFICIENTLY TEST A BIT IN A WORD TO
*         THE RIGHT OF BIT 48. THE BIT NUMBER IS 1 FOR BIT 47, 2 FOR
*         BIT 46, ETC.
          SPACE  4,10 
***       SYMPL CALLING SEQUENCE. 
* 
*         SSBTBW( WORD, BITN, COND) 
* 
*                WORD = WORD TO TEST BIT IN.
* 
*                BITN = BIT NUMBER TO CLEAR.
* 
*                COND = CONDITION OF BIT, 0 IF NOT SET, 1 IF SET. 
 TBW      SPACE  4,10 
 SSBTBW   EQ     *+1S17D
 TBWX     EQU    *
          SA3    A1+1        BIT NUMBER ADDRESS 
          SA2    X1          WORD 
          MX4    -1 
          SA3    X3          BIT NUMBER 
          SB7    X3+12       FOR SHIFT TO BIT 0 
          SA5    A1+2        COND ADDRESS 
          LX2    B7          POSITION WORD
          BX6    -X4*X2      EXTRACT BIT
          SA6    X5          STORE RESULT 
          EQ     TBWX        RETURN 
          END