mpy_32_v_reg.asm

基于TMS320F2812的AMR+RS编解码+OFDM调制解调源程序。是stand alone运行版本

***************************************************************************
** Description:     mpy_32_v_reg() in oper_32b.c                            
**     
** Inputs:                                                                
**          *AR1:	Word16 hi1       : hi part of first number             
**          *AR2:	Word16 lo1       : low part of first number            
**          *AR3:	Word16 hi2       : hi part of second number            
**          *AR4:	Word16 lo2       : low part of second number           
**
** Outputs:                                                                
**								                                           
** Return value:    			                                           
**          
**			ACC:  Word32 L_32                                     
**
** Attribute:       Cycles:          Pm:                               
**                                                                         
** Modified Registers: ACC,P,T                                                 
**                                                                         
** Programmer: Liu Yang
** 
** Complete time: 2002 3 17 
***************************************************************************

	    .global	 _mpy_32_v_reg

_mpy_32_v_reg:

		ZAPA
		MOV		T,@AR1				; T = max_h
        MPY    	P,T,@AR3	  		; P = max_h * ener_h
        MPYA    P,T,@AR4	    	; ACC = P, P = max_h * ener_l
	    MOVH    AR4,P               ; AR4 = PH: get upper 16bit 
	    ADD     ACC,AR4 << #1      	; Perform accumulate
	    MOV	    T,@AR2				; T = max_l	
	    MPY	    P,T,@AR3            ; P = max_l * ener_h
	    MOVH    AR4,P   			; AR4 = PH: get upper 16bit
	    ADD     ACC,AR4	<< #1	    ; Perform final accumulate
	    
	    LRETR