TM的DMC库3.2版数据采样问题
void F281X_ileg2_dcbus_drv_read(ILEG2DCBUSMEAS *p){
int16 DatQ15;
int32 Tmp;
// Wait until ADC conversion is completed
while (AdcRegs.ADCST.bit.SEQ1_BSY == 1)
{};
//AdcRegs.ADCRESULT0×a»»½á1û»o3åÇø
DatQ15 = AdcRegs.ADCRESULT0^0x8000; // Convert raw result to Q15 (bipolar signal)
Tmp = (int32)p->ImeasAGain*(int32)DatQ15; // Tmp = gain*dat => Q28 = Q13*Q15
p->ImeasA = (int16)(Tmp>>13); // Convert Q28 to Q15
p->ImeasA += p->ImeasAOffset; // Add offset
p->ImeasA *= -1; // Positive direction, current flows to motor
DatQ15 = AdcRegs.ADCRESULT1^0x8000; // Convert raw result to Q15 (bipolar signal)
Tmp = (int32)p->ImeasBGain*(int32)DatQ15; // Tmp = gain*dat => Q28 = Q13*Q15
p->ImeasB = (int16)(Tmp>>13); // Convert Q28 to Q15
p->ImeasB += p->ImeasBOffset; // Add offset
p->ImeasB *= -1; // Positive direction, current flows to motor
DatQ15 = (AdcRegs.ADCRESULT2>>1)&0x7FFF; // Convert raw result to Q15 (unipolar signal)
Tmp = (int32)p->VdcMeasGain*(int32)DatQ15; // Tmp = gain*dat => Q28 = Q13*Q15
if (Tmp > 0x0FFFFFFF) // Limit Tmp to 1.0 in Q28
Tmp = 0x0FFFFFFF;
p->VdcMeas = (int16)(Tmp>>13); // Convert Q28 to Q15
p->VdcMeas += p->VdcMeasOffset; // Add offset ìí
p->ImeasC = -(p->ImeasA + p->ImeasB); // Compute phase-c current
AdcRegs.ADCTRL2.all |= 0x4040; // Reset the sequence
}
在上面的处理中，为什么0X8000异或就能转换成双极性的Q15格式了呢，有人知道什么原理嘛，能详细讲解下嘛
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