7.5.1.2 Position Counter Reset on Maximum Position (QEPCTL[PCRM]=01)
If the position counter is equal to QPOSMAX, then the position counter is reset to 0 on the next eQEP clock
for forward movement and position counter overflow flag is set. If the position counter is equal to ZERO, then
the position counter is reset to QPOSMAX on the next QEP clock for reverse movement and position-counter
underflow flag is set.
shows the position-counter reset operation in this mode.
The first index marker fields (QEPSTS[FIDF] and QEPSTS[FIMF]) are not applicable in this mode.
QA
QB
QCLK
QDIR
QPOSCNT
OV/UF
QA
QB
QCLK
QDIR
QPOSCNT
OV/UF
1
2
3
4
0
1
2
1
0
4
3
2
1
0
4
3
2
1
2
3
4
0
1
0
4
3
2
1
0
1
2
3
4
0
1
2
3
4
0
1
0
4
3
Figure 7-9. Position Counter Underflow/Overflow (QPOSMAX = 4)
7.5.1.3 Position Counter Reset on the First Index Event (QEPCTL[PCRM] = 10)
If the index event occurs during forward movement, then the position counter is reset to 0 on the next eQEP
clock. If the index event occurs during the reverse movement, then the position counter is reset to the value
in the QPOSMAX register on the next eQEP clock. Note that this is done only on the first occurrence and
subsequently the position-counter value is not reset on an index event; rather, it is reset based on maximum
position as described in
.
The first index marker fields (QEPSTS[FIDF] and QEPSTS[FIMF]) are not applicable in this mode.
Enhanced Quadrature Encoder Pulse (eQEP)
SPRUH18I – JANUARY 2011 – REVISED JUNE 2022
TMS320x2806x Microcontrollers
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Summary of Contents for TMS320 2806 Series
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