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5409的McBSP配置成SPI口的小结

菜鸟
2008-08-21 17:03:51     打赏


终于把5409的McBSP的配置搞清楚了!现在就把我做的写出来,也好让后来人在这方面少走弯路。我的目标是将MCBSP配置成SPI兼容接口。
        我采用MCBSP0。  下面我把我用汇编写的McBSP的初始化程序给出来。已经调试通过了,但是可能还有不对的地方,请大家看了以后指正!
                .include        "cpu_reg.inc"
                .def            McBsp0Init
McBsp0Init:                    
                stm             #spcr10,spsa0   ;接收复位
                stm             #0000h,spsd0   
               
                stm     #spcr20,spsa0  
                stm     #0000h,spsd0    ;发送复位
                rpt             #9
                nop
                STM             #spcr10,spsa0
                STM             #1800h,spsd0    ;clkstp=11b
*---------------------------PCR0------------------------------------           
                stm             #pcr0,spsa0      ;CLKXP=0,CLKXM=1,FSXM=1,FSXP=1
                                ;xx..............;RESERVED
                                ;..0.............;XIOEN=0时,DS,FSX,CLKX配置为串行接口
                                ;...0............;RIOEN=0时,DR,FSR,CLKR,CLKS配置为串行接口引脚
                                ;....1...........;FSXM=1时,采样率发生器的帧同步模式位(SRGR2的FSGM位)决定帧同步信号
                                ;.....0..........;FSRM=1,片内采样率发生器产生帧同步信号,FSR为输出引脚(除非SRGR的GSYNC=1)
                                ;......1.........;在SPI模式下,CLKXM=1时,McBSP为主设备,并产生时钟(CLKX)
                                                                        ;去驱动它的接收时钟(CLKR)和系统的SPI从设备的SCLK时钟
                                ;.......1........;DLB=0时,
                                                                        ;CLKRM=0,接收时钟由外部时钟驱动
                                                                        ;CLKRM=1,接收时钟由内部采样率发生器驱动
                                                                 ;DLB=1时,
                                                                        ;CLKRM=0,接收时钟由发送时钟驱动,CLKX的特性由PCR的CLKXM位
                                                                        ;设定。CLKR引脚为高阻态
                                                                        ;CLKRM=1,CLKR为由发送时钟(CLKX)驱动的输出引脚。CLKX的特性由PCR的CLKXM位
                                                                        ;设定。
                                ;........x.......;RESERVED,
                                ;.........x......;CLKS引脚状态位。当CLKS被选作通用输入时,该位反映了CLKX引脚的值
                                ;..........x.....;DX引脚状态位
                                ;...........x....;DR引脚状态位
                                ;............1...;帧同步脉冲FSX低电平有效
                                ;.............0..;帧同步脉冲FSR低电平有效
                                ;..............0.;发送时钟极性,CLKXP=0时,在CLKX的上升沿采样发送数据
                                ;...............0;接收时钟极性,CLKRP=0时,在CLKR的上升沿采样发送数据
                stm             #0b08h,spsd0
*-------------------SRGR20-----------------------------------          
                stm             #srgr20,spsa0
                                ;0...............;GSYNC=0,采样率发生寄存器时钟(CLKG)自由运行
                                ;.0..............;CLKSP=0,在CLKS的上升沿产生CLKG和FSG
                                ;..1.............;CLKSM=1,采样率发生器时钟由CPU时钟驱动
                                ;...0............;FSGM=0,当DXR复制到XSR而产生发送帧同步信号(FSX)
                                                                        ;FSGM=0时,FPER和FWID均被忽略
                                ;....xxxxxxxxxxxx;FPER,帧周期
                stm             #2000h,spsd0    ;clksm=1,fsgm=0
*--------------------SRGR10----------------------------------          
                stm             #srgr10,spsa0   ;DSP时钟为60MHz,MBF200为12MHz
                                ;xxxxxxxx........;FWID,帧宽度
                                ;........00110000;CLKDV=48,采样率发生时钟除法器
                stm             #0030h,spsd0    ;clkgdv=30h,SPI的时钟=DSP时钟/48
                                                                ;=1MHz
                nop
                nop
*----------------------RCR10----------------------------------         
                stm             #rcr10,spsa0   
                                ;x...............;RESERVED
                                ;.0000000........;RFLEN1=000 0000,每帧1字
                                ;........100.....;RWDLEN1=100,每字24bit
                                ;...........xxxxx;RESERVED
                stm             #0080h,spsd0   
*---------------------RCR20------------------------------------        
                stm             #rcr20,spsa0
                                ;0...............;RPHASE=0,单相帧
                                ;.0000000........;RFLEN2=000 0000,每帧1字
                                ;........100.....;RWDLEN2=100,每个字24bit
                                ;...........00...;RCOMPAND=00,无扩展,数据传送从最高位(msb)开始
                                ;.............0..;RFIG=0,第一个后的接收帧同步脉冲重新启动数据传送
                                ;..............01;RDATDLY=01,延迟一位数据
                stm             #0081h,spsd0    ;rdatdly=01
*-------------------------XCR10----------------------------------              
                stm             #xcr10,spsa0            ;发送
                                ;x...............;reserved
                                ;.0000000........;XFRLEN1=000 0000,每帧1字
                                ;........100.....;XWDLEN1=100,每字24bit
                                ;...........XXXXX;RESERVED
                stm             #0080h,spsd0    ;
*-------------------------XCR20----------------------------------              
                stm             #xcr20,spsa0            ;发送
                                ;0...............;XPHASE=0,单相帧
                                ;.0000000........;XFLEN2=000 0000,每帧1字
                                ;........100.....;XWDLEN2=100,每字24bit
                                ;...........00...;XCOMPAND=00,无扩展,数据传输从最高位(MSB)开始
                                ;.............0..;SFIG=0,第一个后的发送帧同步脉冲重新启动数据传送
                                ;..............01;XDATDLY=01,延迟一位数据
                stm             #0081h,spsd0   
*-----------------------SPCR20----------------------------------------
                STM             #spcr20,spsa0
                STM             #0040h,spsd0    ;grst=1        
                rpt             #9
                nop                                     ;等待
*---------------------------SPCR10---------------------------------------
                stm             #spcr10,spsa0   ;RINTM=10
                                ;0...............;DLB=0,禁止循环返回
                                ;.00.............;RJUST=00,DRR靠右对齐,高位补0
                                ;...11...........;CLSTP=11,时钟停止模式,有延时
                                ;.....xxx........;RESERVED
                                ;........0.......;DXENA=0,DX使能关
                                ;.........0......;ABIS=0,禁止ABIS模式
                                ;..........10....;RINTM=10,接收中断RINT由一个新的帧同步信号产生
                                ;............0...;RSYNCERR=0,无接收同步错误
                                ;.............0..;RFULL=0,RBR没有出现上溢
                                ;..............0.;RRDY=0,接收器没有准备好
                                ;...............1;RRST=1,打开串口接收
                stm     #9821h, spsd0  
                rpt             #9
                nop
*----------------------------SPCR20----------------------------------
                stm     #spcr20,spsa0  
                                ;xxxxxx..........;RESERVED
                                ;......0.........;FREE=1,时钟自由运行
                                ;.......0........;SOFT=0,禁止SOFT模式
                                ;........0.......;FRST=0,帧同步逻辑电路复位。采样率发生器不会产生帧同步信号FSG
                                ;.........1......;GRST=1,采样率发生器从复位中退出。CLKG按照采样率发生寄存器
                                                                 ;(SRGR)中的编程值产生时钟信号
                                ;..........10....;XINTM=10,发送中断XINT由一个新的帧同步信号产生
                                ;............0...;XSYNCERR=0,无发送帧帧同步错误
                                ;.............0..;XEMPTY=0,XSR为空
                                ;..............0.;XRDY=0,发送器未准备好
                                ;...............1;XRST=1,打开串口发送
                stm     #0061h,spsd0   
                rpt             #9
                nop
                stm             #spcr20,spsa0   ;FRST=1
                orm             #0080h,spsd0
                rpt             #6
                nop
                ret
 




关键词: McBSP     配置     小结     spsa0     接收     spsd    

高工
2020-04-14 14:36:36     打赏
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学习一下


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