Enhanced Quadrature Encoder Pulse (eQEP) Module
15.4.3.20 eQEP Status Register (QEPSTS)
Figure 15-168. eQEP Status Register (QEPSTS)
15
8
Reserved
R-0
7
6
5
4
3
2
1
0
UPEVNT
FIDF
QDF
QDLF
COEF
CDEF
FIMF
PCEF
R-0
R-0
R-0
R-0
R/W-1
R/W-1
R/W-1
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 15-143. eQEP Status Register (QEPSTS) Field Descriptions
Bit
Field
Value
Description
15-8
Reserved
0
Always write as 0
7
UPEVNT
Unit position event flag
0
No unit position event detected
1
Unit position event detected. Write 1 to clear.
6
FDF
Direction on the first index marker. Status of the direction is latched on the first index event marker.
0
Counter-clockwise rotation (or reverse movement) on the first index event
1
Clockwise rotation (or forward movement) on the first index event
5
QDF
Quadrature direction flag
0
Counter-clockwise rotation (or reverse movement)
1
Clockwise rotation (or forward movement)
4
QDLF
eQEP direction latch flag. Status of direction is latched on every index event marker.
0
Counter-clockwise rotation (or reverse movement) on index event marker
1
Clockwise rotation (or forward movement) on index event marker
3
COEF
Capture overflow error flag
0
Sticky bit, cleared by writing 1
1
Overflow occurred in eQEP Capture timer (QEPCTMR)
2
CDEF
Capture direction error flag
0
Sticky bit, cleared by writing 1
1
Direction change occurred between the capture position event.
1
FIMF
First index marker flag
0
Sticky bit, cleared by writing 1
1
Set by first occurrence of index pulse
0
PCEF
Position counter error flag. This bit is not sticky and it is updated for every index event.
0
No error occurred during the last index transition.
1
Position counter error
1687
SPRUH73H – October 2011 – Revised April 2013
Pulse-Width Modulation Subsystem (PWMSS)
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