*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