main.asm

VC5402的MCBSP作为通用串口的程序

 				 .global  main_start
 				 .global  _McBSP_init
                 .global    _init_54 
				 .mmregs
                 .include "init_54x.inc" ;包含VC5402初始化的各个寄存器
                 .include "mcbsp54x.inc" ;多通道缓冲串行口的各个寄存器
K_IPTR_init     .set  0080h
GPIOCR 			.set 3Ch 
GPIOSR 			.set 3Dh 
                .text
            	.def	_c_int00
_c_int00:
main_start:
***************初始化系统***************************
_init_54:     
 				NOP
				LD 		#0, DP     ;复位数据页指针
****************使所有的中断无效******************************
				SSBX   INTM        ;屏蔽全局中断
				STM    #0x0000,IMR ;屏蔽所有的中断
				STM    #0x0FFFF,IFR ;清除中断标志寄存器
****************时钟方案选择**********************************
           		STM		#0, CLKMD	;DSP系统时钟的软件设置
				STM     #0,	CLKMD   
				STM		#0x9007,CLKMD ;设置VC5402 DSP时钟到5MHz
****************配置C5402系统寄存器*******************************
				STM		#0x7492,SWWSR ;I/O等待2个时钟，数据和程序空间无等待
				STM     #0x0000,BSCR  ;为块切换等待0个时钟
				STM     #0x1800,ST0
				STM		#0x2900,ST1
				STM		#0x0FFE0,PMST  ;0x0FFA0
****************改变中断向量表位置*****************************
			    LDM   PMST,        A
		   		AND   #7FH,        A 
		   		OR    #K_IPTR_init,     A 
		   		STLM  A,           		PMST
				NOP
				NOP

_HPI_8_IO:
				STM #0FFh, GPIOCR 
				STM #0AAh, GPIOSR 
				NOP
				NOP
_McBSP_init:
*********************串行端口复位******************************************
				STM		#SPCR10_SUBADDR,SPSA0 ;复位串行端口
				STM		#0000h,SPSD0        ;/RRST=0 ;控制寄存器1配置
				STM		#SPCR20_SUBADDR,SPSA0
				STM		#0000h,SPSD0        ;/XRST=0 ;控制寄存器2配置			
				RPT		#512
				NOP 
				
				STM		#PCR0_SUBADDR,SPSA0   
				STM		#3F25h,SPSD0   
				
				RPT		#512
				NOP        
		
	.end