X=N x P
P
QA
QB
QCLK
UPEVNT
QCAPCTL:CEN
Capture timer
control unit
(CTCU)
QCPRD
QCTMR
QCTMRLAT
QCPRDLAT
16
16
3-bit binary
divider
x1, 1/2, 1/4...,
1/128
CAPCLK
QCAPCTL:CCPS
3
SYSCLKOUT
16
0xFFFF
16
QEPSTS:COEF
x1, 1/2, 1/4...,
1/2048
4-bit binary
divider
QCLK
Rising/falling
edge detect
QDIR
QEPSTS:CDEF
QEPCTL:UTE
QUTMR
QUPRD
SYSCLKOUT
QFLG:UTO
UTIME
4
QCAPCTL:UPPS
UTOUT
QEPSTS:UPEVNT
UPEVNT
eQEP Edge Capture Unit
837
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
C28 Enhanced QEP (eQEP) Module
Figure 9-15. eQEP Edge Capture Unit
NOTE:
The QCAPCTL[UPPS] prescaler should not be modified dynamically (such as switching the
unit event prescaler from QCLK/4 to QCLK/8). Doing so may result in undefined behavior.
The QCAPCTL[CPPS] prescaler can be modified dynamically (such as switching CAPCLK
prescaling mode from SYSCLK/4 to SYSCLK/8) only after the capture unit is disabled.
Figure 9-16. Unit Position Event for Low Speed Measurement (QCAPCTL[UPPS] = 0010)
A
N - Number of quadrature periods selected using QCAPCTL[UPPS] bits