A51 MACRO ASSEMBLER  STARTUP                                                              12/01/2007 15:27:30 PAGE     1


MACRO ASSEMBLER A51 V6.12
OBJECT MODULE PLACED IN STARTUP.OBJ
ASSEMBLER INVOKED BY: C:\Keil\C51\BIN\A51.EXE STARTUP.A51 SET(SMALL) DEBUG EP

LOC  OBJ            LINE     SOURCE

                       1     ;------------------------------------------------------------------------------
                       2     ;  This file is part of the C51 Compiler package
                       3     ;  Copyright (c) 1988-1999 Keil Elektronik GmbH and Keil Software, Inc.
                       4     ;------------------------------------------------------------------------------
                       5     ;  STARTUP.A51:  This code is executed after processor reset.
                       6     ;
                       7     ;  To translate this file use A51 with the following invocation:
                       8     ;
                       9     ;     A51 STARTUP.A51
                      10     ;
                      11     ;  To link the modified STARTUP.OBJ file to your application use the following
                      12     ;  BL51 invocation:
                      13     ;
                      14     ;     BL51 <your object file list>, STARTUP.OBJ <controls>
                      15     ;
                      16     ;------------------------------------------------------------------------------
                      17     ;
                      18     ;  User-defined Power-On Initialization of Memory
                      19     ;
                      20     ;  With the following EQU statements the initialization of memory
                      21     ;  at processor reset can be defined:
                      22     ;
                      23     ;               ; the absolute start-address of IDATA memory is always 0
  0080                24     IDATALEN        EQU     80H     ; the length of IDATA memory in bytes.
                      25     ;
  0000                26     XDATASTART      EQU     0H      ; the absolute start-address of XDATA memory
  0000                27     XDATALEN        EQU     0H      ; the length of XDATA memory in bytes.
                      28     ;
  0000                29     PDATASTART      EQU     0H      ; the absolute start-address of PDATA memory
  0000                30     PDATALEN        EQU     0H      ; the length of PDATA memory in bytes.
                      31     ;
                      32     ;  Notes:  The IDATA space overlaps physically the DATA and BIT areas of the
                      33     ;          8051 CPU. At minimum the memory space occupied from the C51 
                      34     ;          run-time routines must be set to zero.
                      35     ;------------------------------------------------------------------------------
                      36     ;
                      37     ;  Reentrant Stack Initilization
                      38     ;
                      39     ;  The following EQU statements define the stack pointer for reentrant
                      40     ;  functions and initialized it:
                      41     ;
                      42     ;  Stack Space for reentrant functions in the SMALL model.
  0000                43     IBPSTACK        EQU     0       ; set to 1 if small reentrant is used.
  0100                44     IBPSTACKTOP     EQU     0FFH+1  ; set top of stack to highest location+1.
                      45     ;
                      46     ;  Stack Space for reentrant functions in the LARGE model.      
  0000                47     XBPSTACK        EQU     0       ; set to 1 if large reentrant is used.
  0000                48     XBPSTACKTOP     EQU     0FFFFH+1; set top of stack to highest location+1.
                      49     ;
                      50     ;  Stack Space for reentrant functions in the COMPACT model.    
  0000                51     PBPSTACK        EQU     0       ; set to 1 if compact reentrant is used.
  0000                52     PBPSTACKTOP     EQU     0FFFFH+1; set top of stack to highest location+1.
                      53     ;
                      54     ;------------------------------------------------------------------------------
                      55     ;
                      56     ;  Page Definition for Using the Compact Model with 64 KByte xdata RAM
                      57     ;
                      58     ;  The following EQU statements define the xdata page used for pdata
A51 MACRO ASSEMBLER  STARTUP                                                              12/01/2007 15:27:30 PAGE     2

                      59     ;  variables. The EQU PPAGE must conform with the PPAGE control used
                      60     ;  in the linker invocation.
                      61     ;
  0000                62     PPAGEENABLE     EQU     0       ; set to 1 if pdata object are used.
  0000                63     PPAGE           EQU     0       ; define PPAGE number.
                      64     ;
                      65     ;------------------------------------------------------------------------------
                      66     
                      67                     NAME    ?C_STARTUP
                      68     
                      69     
                      70     ?C_C51STARTUP   SEGMENT   CODE
                      71     ?STACK          SEGMENT   IDATA
                      72     
----                  73                     RSEG    ?STACK
0000                  74                     DS      1
                      75     
                      76                     EXTRN CODE (?C_START)
                      77                     PUBLIC  ?C_STARTUP
                      78     
----                  79                     CSEG    AT      0
0000 020000   F       80     ?C_STARTUP:     LJMP    STARTUP1
                      81     
----                  82                     RSEG    ?C_C51STARTUP
                      83     
0000                  84     STARTUP1:
                      85     
                      86     IF IDATALEN <> 0
0000 787F             87                     MOV     R0,#IDATALEN - 1
0002 E4               88                     CLR     A
0003 F6               89     IDATALOOP:      MOV     @R0,A
0004 D8FD             90                     DJNZ    R0,IDATALOOP
                      91     ENDIF
                      92     
                      93     IF XDATALEN <> 0
                                             MOV     DPTR,#XDATASTART
                                             MOV     R7,#LOW (XDATALEN)
                               IF (LOW (XDATALEN)) <> 0
                                             MOV     R6,#(HIGH (XDATALEN)) +1
                               ELSE
                                             MOV     R6,#HIGH (XDATALEN)
                               ENDIF
                                             CLR     A
                             XDATALOOP:      MOVX    @DPTR,A
                                             INC     DPTR
                                             DJNZ    R7,XDATALOOP
                                             DJNZ    R6,XDATALOOP
                             ENDIF
                     107     
                     108     IF PPAGEENABLE <> 0
                                             MOV     P2,#PPAGE
                             ENDIF
                     111     
                     112     IF PDATALEN <> 0
                                             MOV     R0,#PDATASTART
                                             MOV     R7,#LOW (PDATALEN)
                                             CLR     A
                             PDATALOOP:      MOVX    @R0,A
                                             INC     R0
                                             DJNZ    R7,PDATALOOP
                             ENDIF
                     120     
                     121     IF IBPSTACK <> 0
                             EXTRN DATA (?C_IBP)
                             
                                             MOV     ?C_IBP,#LOW IBPSTACKTOP
A51 MACRO ASSEMBLER  STARTUP                                                              12/01/2007 15:27:30 PAGE     3

                             ENDIF
                     126     
                     127     IF XBPSTACK <> 0
                             EXTRN DATA (?C_XBP)
                             
                                             MOV     ?C_XBP,#HIGH XBPSTACKTOP
                                             MOV     ?C_XBP+1,#LOW XBPSTACKTOP
                             ENDIF
                     133     
                     134     IF PBPSTACK <> 0
                             EXTRN DATA (?C_PBP)
                                             MOV     ?C_PBP,#LOW PBPSTACKTOP
                             ENDIF
                     138     
0006 758100   F      139                     MOV     SP,#?STACK-1
                     140     EXTRN CODE (?B_SWITCH0)
0009 120000   F      141                     CALL    ?B_SWITCH0      ; init bank mechanism to code bank 0
000C 020000   F      142                     LJMP    ?C_START
                     143     
                     144                     END
A51 MACRO ASSEMBLER  STARTUP                                                              12/01/2007 15:27:30 PAGE     4

SYMBOL TABLE LISTING
------ ----- -------


N A M E             T Y P E  V A L U E   ATTRIBUTES

?B_SWITCH0 . . . .  C ADDR   -----       EXT
?C_C51STARTUP. . .  C SEG    000FH       REL=UNIT
?C_START . . . . .  C ADDR   -----       EXT
?C_STARTUP . . . .  C ADDR   0000H   A   
?STACK . . . . . .  I SEG    0001H       REL=UNIT
IBPSTACK . . . . .  N NUMB   0000H   A   
IBPSTACKTOP. . . .  N NUMB   0100H   A   
IDATALEN . . . . .  N NUMB   0080H   A   
IDATALOOP. . . . .  C ADDR   0003H   R   SEG=?C_C51STARTUP
PBPSTACK . . . . .  N NUMB   0000H   A   
PBPSTACKTOP. . . .  N NUMB   0000H   A   
PDATALEN . . . . .  N NUMB   0000H   A   
PDATASTART . . . .  N NUMB   0000H   A   
PPAGE. . . . . . .  N NUMB   0000H   A   
PPAGEENABLE. . . .  N NUMB   0000H   A   
SP . . . . . . . .  D ADDR   0081H   A   
STARTUP1 . . . . .  C ADDR   0000H   R   SEG=?C_C51STARTUP
XBPSTACK . . . . .  N NUMB   0000H   A   
XBPSTACKTOP. . . .  N NUMB   0000H   A   
XDATALEN . . . . .  N NUMB   0000H   A   
XDATASTART . . . .  N NUMB   0000H   A   


REGISTER BANK(S) USED: 0 


ASSEMBLY COMPLETE.  0 WARNING(S), 0 ERROR(S)
