dsp281x_codestartbranch.asm

能够实现PWM输出功能

;//###########################################################################
;//
;// FILE:  DSP281x_CodeStartBranch.asm	
;//
;// TITLE: Branch for redirecting code execution after boot. 
;//
;//###########################################################################
;//
;//  Ver | dd mmm yyyy | Who  | Description of changes
;// =====|=============|======|===============================================
;//  1.00| 11 Sep 03   | L.H. | Updated based on D.A source to allow 
;//      |             |      | disabling the watchdog before branching to
;//      |             |      | the C init routine.  This is useful if the
;//      |             |      | watchdog is timing out before main() is reached.
;//########################################################################### 	


***********************************************************************




* WD_DISABLE	.set	1		;set to 1 to disable WD, else set to 0

  .ref  _c_int00

***********************************************************************
* Function: codestart section
*
* Description: Branch to code starting point
***********************************************************************

  .sect   "codestart"


_code_start:
*     .if WD_DISABLE == 1
*        LB wd_disable       ;Branch to watchdog disable code
*     .else
        LB  _c_int00        ;Branch to start of boot.asm in RTS library
*     .endif

;end codestart section


***********************************************************************
*  Function: wd_disable
*
*  Description: Disables the watchdog timer
***********************************************************************
*   .if WD_DISABLE == 1

*    .text
*   wd_disable:
*   SETC OBJMODE        ;Set OBJMODE for 28x object code
*    EALLOW              ;Enable EALLOW protected register access
*    MOVZ DP, #7029h>>6  ;Set data page for WDCR register
*    MOV @7029h, #0068h  ;Set WDDIS bit in WDCR to disable WD
*    EDIS                ;Disable EALLOW protected register access
*    LB _c_int00         ;Branch to start of boot.asm in RTS library

*   .endif

;end wd_disable


   .end
	
; end of file CodeStartBranch.asm