startu32.a51

Keil3_Full

$NOMOD51
;------------------------------------------------------------------------------
;  STARTU32.A51:  This code is executed after processor reset.
;    
;  Modified for uPSD Startup:
;     - Disable Watchdog timer - enable at beginning of user application
;     - Settup various IP prescalers to large values (lowers power requirements)
;       The IP device drivers wil need to initialize the prescaler to the right value
;
;------------------------------------------------------------------------------


;  User-defined Power-On Initialization of Memory (Clear Memory)
;
;  With the following EQU statements the initialization of memory
;  at processor reset can be defined:

;               ; the absolute start-address of IDATA memory is always 0
IDATALEN        EQU     100H    ; the length of IDATA memory in bytes.

; *** NOTE: uPSD users need to fill in the following based on where SRAM memory mapped.

XDATASTART      EQU     0H      ; the absolute start-address of XDATA memory
XDATALEN        EQU     0H      ; the length of XDATA memory in bytes.

PDATASTART      EQU     0H      ; the absolute start-address of PDATA memory
PDATALEN        EQU     0H      ; the length of PDATA memory in bytes.

;  Notes:  The IDATA space overlaps physically the DATA and BIT areas of the
;          8051 CPU. At minimum the memory space occupied from the C51 
;          run-time routines must be set to zero.


;------------------------------------------------------------------------------
;
;  Reentrant Stack Initilization
;
;  The following EQU statements define the stack pointer for reentrant
;  functions and initialized it:
;
;  Stack Space for reentrant functions in the SMALL model.
IBPSTACK        EQU     0       ; set to 1 if small reentrant is used.
IBPSTACKTOP     EQU     0FFH+1  ; set top of stack to highest location+1.
;
;  Stack Space for reentrant functions in the LARGE model.      
XBPSTACK        EQU     0       ; set to 1 if large reentrant is used.
XBPSTACKTOP     EQU     0FFFFH+1; set top of stack to highest location+1.
;
;  Stack Space for reentrant functions in the COMPACT model.    
PBPSTACK        EQU     0       ; set to 1 if compact reentrant is used.
PBPSTACKTOP     EQU     0FFFFH+1; set top of stack to highest location+1.
;
;------------------------------------------------------------------------------
;
;  Page Definition for Using the Compact Model with 64 KByte xdata RAM
;
;  The following EQU statements define the xdata page used for pdata
;  variables. The EQU PPAGE must conform with the PPAGE control used
;  in the linker invocation.
;
PPAGEENABLE     EQU     0       ; set to 1 if pdata object are used.
;
PPAGE           EQU     0       ; define PPAGE number.
;
PPAGE_SFR       DATA    0A0H    ; SFR that supplies uppermost address byte
;               (most 8051 variants use P2 as uppermost address byte)
;
;------------------------------------------------------------------------------

; Standard SFR Symbols 
ACC     DATA    0E0H
B       DATA    0F0H
SP      DATA    81H
DPL     DATA    82H
DPH     DATA    83H
BUSCON  DATA    9DH


                NAME    ?C_STARTUP


?C_C51STARTUP   SEGMENT   CODE
?STACK          SEGMENT   IDATA

                RSEG    ?STACK
                DS      1

                EXTRN CODE (?C_START)
                PUBLIC  ?C_STARTUP

                CSEG    AT      0
?C_STARTUP:     LJMP    STARTUP1

                RSEG    ?C_C51STARTUP

STARTUP1:

; Turbo uPSD specific initialization

;		MOV     A, #0FEH	; Load pre-scalars with large value
;		MOV     ASCL, A		; Slow down ADC Logic
;		MOV     PSCL0L, A	; Slow down PWM Logic
;		MOV     PSCL0H, A
;		MOV     PSCL1L, A
;		MOV     PSCL1H, A
;		MOV     USCL, A		; Slow down USB Logic

;		MOV     A, #055H	; Disable Watch Dog Reset
;		MOV     WDKEY, A

;		MOV	A, 0		; Disable DDC and DDC XRAM out of addr space
;                MOV     DDCCON, A
;		MOV     S1CON, A	; Disable DDC I2C as well


IF IDATALEN <> 0
                MOV     R0,#IDATALEN - 1
                CLR     A
IDATALOOP:      MOV     @R0,A
                DJNZ    R0,IDATALOOP
ENDIF

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

IF PPAGEENABLE <> 0
                MOV     PPAGE_SFR,#PPAGE
ENDIF

IF PDATALEN <> 0
                MOV     R0,#LOW (PDATASTART)
                MOV     R7,#LOW (PDATALEN)
                CLR     A
PDATALOOP:      MOVX    @R0,A
                INC     R0
                DJNZ    R7,PDATALOOP
ENDIF

IF IBPSTACK <> 0
EXTRN DATA (?C_IBP)

                MOV     ?C_IBP,#LOW IBPSTACKTOP
ENDIF

IF XBPSTACK <> 0
EXTRN DATA (?C_XBP)

                MOV     ?C_XBP,#HIGH XBPSTACKTOP
                MOV     ?C_XBP+1,#LOW XBPSTACKTOP
ENDIF

IF PBPSTACK <> 0
EXTRN DATA (?C_PBP)
                MOV     ?C_PBP,#LOW PBPSTACKTOP
ENDIF

                MOV     SP,#?STACK-1
; This code is required if you use L51_BANK.A51 with Banking Mode 4
; EXTRN CODE (?B_SWITCH0)
;               CALL    ?B_SWITCH0      ; init bank mechanism to code bank 0
                LJMP    ?C_START

                END