TMS320F28069中EQEP单位时间和位置计数锁存问题

在使用EQEP用于M/T方法测速时

If the QEPCTL[QCLM] bit is cleared, then the capture timer and capture period values are latched into the
QCTMRLAT and QCPRDLAT registers, respectively, when the CPU reads the position counter
(QPOSCNT).If the QEPCTL[QCLM] bit is set, then the position counter, capture timer, and capture period values are
latched into the QPOSLAT, QCTMRLAT and QCPRDLAT registers, respectively, on unit time out.根据数据手册给说明，将QEPCTL[QCLM]设置为0，在通过CPU连续读4次读取QPOSCNT的值，发现第三次读取的值，比别的3次数据值小于1，不知道怎么回事？请问说明原因导致的

mangui zhang：除了溢出外应该都是后面的比前面的数大

在使用EQEP用于M/T方法测速时

If the QEPCTL[QCLM] bit is cleared, then the capture timer and capture period values are latched into the
QCTMRLAT and QCPRDLAT registers, respectively, when the CPU reads the position counter
(QPOSCNT).If the QEPCTL[QCLM] bit is set, then the position counter, capture timer, and capture period values are
latched into the QPOSLAT, QCTMRLAT and QCPRDLAT registers, respectively, on unit time out.根据数据手册给说明，将QEPCTL[QCLM]设置为0，在通过CPU连续读4次读取QPOSCNT的值，发现第三次读取的值，比别的3次数据值小于1，不知道怎么回事？请问说明原因导致的

guang long1：

回复 mangui zhang:

GlobM_T_Calc.QposcntNumBuf1=EQep1Regs.QPOSCNT;GlobM_T_Calc.QposcntNumBuf2=EQep1Regs.QPOSCNT;GlobM_T_Calc.QposcntNumBuf3=EQep1Regs.QPOSCNT;GlobM_T_Calc.QposcntNumBuf4=EQep1Regs.QPOSCNT;
但是我是连续读取四次QPOSCNT的值，结果是第三次读取的数字都比其它的小于1