DSP28335中文资料 - 图文

TMS320F28335 TechV_28335

目录

1 DSP的PWM信号 .................................................................................................................. 1

1．1简介 ................................................................................................................................. 1 1．2端口对应关系 ................................................................................................................. 2 1．3初始化程序注释 ............................................................................................................. 2 2 DSP的CAN通信 ................................................................................................................... 4

2．1CAN2.0B协议简述 ....................................................................................................... 4 2．2CAN总线电平 ............................................................................................................... 5 2．3CAN总线上的120欧电阻 .......................................................................................... 6 2．4DSP的CAN时钟模块 ................................................................................................. 6 2．5邮箱初始化例程注解 ..................................................................................................... 7 2．6消息发送和接收 ............................................................................................................. 8 2．7CAN的适配器存在的一些问题 ................................................................................... 9 3 DSP的32位浮点运算测试 .................................................................................................. 10 4 DSP定时器中断 ..................................................................................................................... 11

4．1 DSP28335的定时器 .................................................................................................. 11 4．2定时器分频 ................................................................................................................... 11 4．3 计数器计数 .................................................................................................................. 12 4．4定时器时钟周期 ........................................................................................................... 12 5 DSP看门狗复位 ..................................................................................................................... 12

5．1看门狗时钟 ................................................................................................................... 12 5．2看门狗系统控制和状态寄存器(SCSR) ...................................................................... 13 5．3看门狗计数寄存器（WDCNTR） ........................................................................... 13 5．4看门狗重启管理器（WDKEY） .............................................................................. 14 5．5看门狗控制寄存器(WDCR) ....................................................................................... 14 6 软件报错与处理 ...................................................................................................................... 15

6．1CCS Setup中仿真器的配置 ....................................................................................... 15 6．2Connect报错——1145——换仿真器解决 ............................................................... 17 6．3CAN口测试A发B收，数据发不出去 ................................................................... 19 6．4编译Pwm测试文件出错............................................................................................ 19 6．5could not open source file \DSP2833x_Device.h ................................................. 20 7 备注与注意事项 ...................................................................................................................... 22 8 附录 C源程序 ...................................................................................................................... 22

8．1PWM初始化及脉冲产生函数 .................................................................................... 22 8．2邮箱初始化函数 ........................................................................................................... 33 8．3浮点运算测试函数 ....................................................................................................... 36 8．4定时器中断初始化函数 ............................................................................................... 38 8．5采用定时器的延时函数 ............................................................................................... 39 8．6看门狗初始化函数 ....................................................................................................... 40

DSP28335测试总结

1 DSP的PWM信号

1．1简介

DSP28335共12路16位的ePWM，能进行频率和占空比控制。 ePWM的时钟TBCLK=SYSCLKOUT/(HSPCLKDIV×CLKDIV):

PWM信号频率由时基周期寄存器TBPDR和时基计数器的计数模式决定。初始化程序采用的计数模式为递增计数模式。在递增计数模式下，时基计数器从零开始增加，直到达到周期寄存器值（TBPDR）。然后时基计数器复位到零，再次开始增加。

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DSP28335测试总结

PWM信号周期与频率的计算如下：

1．2端口对应关系

通道 1 2 3 4 5 6 7 8 9 10 11 12

相应PWM的A/B ePWM１A ePWM１Ｂ ePWM２A ePWM２Ｂ ePWM３A ePWM３Ｂ ePWM４A ePWM４Ｂ ePWM５A ePWM５Ｂ ePWM６A ePWM６Ｂ 对应JP0B端口号 9 10 11 12 13 14 15 16 17 18 19 20 说明：JP0B的端口号按“Z”字形顺序数。

1．3初始化程序注释 void InitPwm1AB(float32 f) {

Uint16 T= 2343750/f-1.0;//系统时钟SYSCLKOUT=150MHz，TBCLK=6.6666667ns，在连续增计数模式下，f=150000000/(TBPDR+1) EALLOW;

//先初始化通用输入输出口//

GpioCtrlRegs.GPAPUD.bit.GPIO0 = 0; GpioCtrlRegs.GPAMUX1.bit.GPIO0 = 1; GpioCtrlRegs.GPAPUD.bit.GPIO1 = 0; GpioCtrlRegs.GPAMUX1.bit.GPIO1 = 1;

EPwm1Regs.TBPHS.half.TBPHS = 0; // 在相位寄存器中设置计数器的起始计数位置

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DSP28335测试总结

//下面两条语句组合对PWM的时钟进行分频 EPwm1Regs.TBCTL.bit.CLKDIV = 6; EPwm1Regs.TBCTL.bit.HSPCLKDIV = 0;

EPwm1Regs.TBPRD = T; //在周期寄存器中设置计数器的计数周期

//TBCTL为定时器控制寄存器

EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; //设置计数模式位为连续增计数模式，产生对称方波

EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE; // 将定时器相位使能位关闭 EPwm1Regs.TBCTL.bit.PRDLD = TB_SHADOW;//映射寄存器SHADOW使能并配置映射寄存器为自动读写

EPwm1Regs.TBCTL.bit.SYNCOSEL = TB_CTR_ZERO; // 定时器时钟源选择，一共有四种时钟源

EPwm1Regs.CMPA.half.CMPA= 0.0001*T;// 设置EPWM1A比较值寄存器的比较值，即体现EPWM1A的占空比 EPwm1Regs.CMPB= 0.0001*T;

EPwm1Regs.CMPCTL.bit.SHDWAMODE = CC_SHADOW;//A模块比较模式 EPwm1Regs.CMPCTL.bit.SHDWBMODE = CC_SHADOW;//B模块比较模式 EPwm1Regs.CMPCTL.bit.LOADAMODE = CC_CTR_ZERO; // A模块比较使能,通过写0来清除SHDWAMODE位来使能load on CTR=Zero

EPwm1Regs.CMPCTL.bit.LOADBMODE = CC_CTR_ZERO; // B模块比较使能，通过写0来清除SHDWBMODE位来使能load on CTR=Zero

//AQCTLA为输出A比较方式控制寄存器

EPwm1Regs.AQCTLA.bit.ZRO = AQ_SET; // TBCTR（计数器）计到零时使输出为反向

EPwm1Regs.AQCTLA.bit.CAU = AQ_CLEAR;//TBCTR（计数器）与CMPA在up计数时相等使输出为high，这关系的输出的占空比 EPwm1Regs.AQCTLB.bit.ZRO = AQ_SET; EPwm1Regs.AQCTLB.bit.CBU = AQ_CLEAR; EDIS; }

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