TMS570LC4357: N2HET PWM

Hi Mingxi,

In the HALCoGen generated HET code,

mingxi liu said:

uint32 pwmPeriod = (hetRAM->Instruction[(cap << 1U) + 26U].Data) >> 7U;

the 26th instruction is: PCNT which is used to capture the period of input signal 0

mingxi liu said:

uint32    pwmPeriod = (hetRAM->Instruction[(pwm << 1U) + 42U].Data + 128U) >> 7U;

the 42th instruction is:  MOV64 which is to update the period of PWM0 which is used by instruction #2  DJZ (remote address). 

Now consider the data field of the MOV64 instruction:

This data field is made up or a 7-bit high-resolution data field and a 25-bit loop-resolution data field. This HALCoGen example does not use the high-resolution capability, so the "HR Data" field is not used. This is why the updated data value is shifted by 7 and then an offset of 128 is added (2^7 = 128).

王工：

     1） 如果我想捕获PWM脉冲的周期period ，应该使用PCNT 还是MOV64 指令？

      2）为什么代码2需要先加128再shifted by 7？而不是直接

      uint32    pwmPeriod = (hetRAM->Instruction[(pwm << 1U) + 42U].Data) >> 7U;