dsp_init.s54

c5x中关于dma的实验

;******************************************************************************
;               		SJTU DSP Tech. Center
;        Copyright (c) 2002 SJTU DSP Tech. Center. All Rights Reserved.
;  History:
;		Date		Authors			Changes
;		2003/08/30	Fu Xuan			Created.
;******************************************************************************
	.mmregs

	.def		DSPInit
;	.ref 		codec_init
	
;	.ref		DATA_STORE_SIZE
;	.ref		INPUT_PINGPONG_0
;	.ref		INPUT_PINGPONG_1
;	.ref		OUTPUT_PINGPONG_0
	
;	.include 	"dsp_cnst.h54"
;	.include	"codec_cnst.h54"
;	.include 	"macro.h54"

	.text
;******************************************************************************
;** Function:	DSPInit()
;** Description:	DSP initialization
;******************************************************************************
DSPInit:

	;set register ST1 to initialize DSP
	;    bit:   15     14   13   12    11    10   9     8     7      6     5     4-0
	;		  | BRAF | CPL | XF | HM | INTM | 0 | OVM | SXM | C16 | FRCT | CMPT | ASM |
	;	   		 x      1    x     x    1     0    1     0     0     1      0    xxxxx
	ssbx	INTM		;close interrupt first
	ssbx	CPL
	rsbx	SXM
	rsbx	C16
	rsbx	CMPT
	ssbx	FRCT
	ssbx	OVM

	;set register PMST
	;    bit:  15-7     6      5      4      3       2       1      0
	;		  | IPTR | MP/MC | OVLY | AVIS | DROM | CLKOFF | SMUL | SST |
	;	  		xxxx     1       1      0      x       x       0     0
	;PMST (IPTR=0x1, /MC=1, OVLY=1, SMUL=0, SST=0)
	stm		#0x00E0, PMST

	;set register SWWSR
	stm		#0x7000, SWWSR	;I/O=7, set the external I/O space access with max wait

	ret
;end of DSPInit

;end of dsp_init.s54