ASMB,L
      HED ".VDRP" - RPL'ING OF:  DVADD DVSUB .... DVSMY DVSDV . 
      NAM .VDRP,7 12824-1X047 REV.2026 800506 
      EXT .DVCT 
      ENT DVADD,DVSUB,DVMPY,DVDIV,DVSAD,DVSSB,DVSMY,DVSDV 
**************************************************************
* 
*     NAME:   .VDRP 
*     SOURCE: 12824-18047 
*     RELOC:  PART OF 12824-12001 
*     PGMR:   BG,CG 
* 
*  ***********************************************************
*  * (C) COPYRIGHT HEWLETT-PACKARD COMPANY 1979.  ALL RIGHTS *
*  * RESERVED.  NO PART OF THIS PROGRAM MAY BE PHOTOCOPIED,  *
*  * REPRODUCED OR TRANSLATED TO ANOTHER PROGRAM LANGUAGE    *
*  * WITHOUT THE PRIOR CONSENT OF HEWLETT-PACKARD COMPANY.   *
*  ***********************************************************
* 
**************************************************************
* 
A     EQU 0 
B     EQU 1 
* 
*     .DVECT REPLACES CALLS TO DVADD...DVSDV WITH THE APPROPRIATE 
*     TWO-WORD OPCODE.  IF THE MAIN OPCODE IS NOT RPL'D, IT FAKES 
*     A JSB INSTEAD OF REPLACING THE ORIGINAL JSB.
* 
DVADD NOP 
      JSB COM 
      OCT 004002
* 
DVSUB NOP 
      JSB COM 
      OCT 004022
* 
DVMPY NOP 
      JSB COM 
      OCT 004042
* 
DVDIV NOP 
      JSB COM 
      OCT 004062
* 
DVSAD NOP 
      JSB COM 
      OCT 004402
* 
DVSSB NOP 
      JSB COM 
      OCT 004422
* 
DVSMY NOP 
      JSB COM 
      OCT 004442
* 
DVSDV NOP 
      JSB COM 
      OCT 004462
* 
COM   NOP 
      LDA COM,I     A = SUB-OPCODE. 
      LDB COM       GET ADDRESS + 1 OF ORIGINAL JSB.
      ADB =D-2
      LDB B,I 
      STA B,I       OVERLAY ORIGINAL RTN PTR WITH SUB-OPCODE. 
      LDA OPCOD     A = MAIN OPCODE.
      SSA,RSS       SOFTWARE ?
      JMP SOFT      YES, SPECIAL CASE.
      ADB =D-1      NO. OVERLAY ORIGINAL JSB WITH MAIN OPCODE.
      STA B,I 
      JMP B,I       GO EXECUTE THE OPCODE.
* 
SOFT  STB A,I       FAKE A JSB TO THE SOFTWARE.  FIRST, RTN ADDR. 
      INA           THEN, 
      JMP A,I        THE ENTRY. 
* 
OPCOD DEF .DVCT+0 
      END 
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