The position-compare match (QFLG[PCM]) is set when the position-counter value (QPOSCNT) matches with the
active position-compare register (QPOSCMP) and the position-compare sync output of the programmable pulse
width is generated on compare-match to trigger an external device.
For example, if QPOSCMP = 2, the position-compare unit generates a position-compare event on 1 to 2
transitions of the eQEP position counter for forward counting direction and on 3 to 2 transitions of the eQEP
position counter for reverse counting direction (see
See the register section for the layout of the eQEP Position-Compare Control Register (QPOSCTL) and
description of the QPOSCTL bit fields.
POSCMP=2
0
1
2
3
4
3
2
1
0
1
2
3
4
3
2
1
0
eQEP counter
PCEVNT
PCSOUT (active HIGH)
PCSOUT (active LOW)
PCSPW
Figure 7-13. eQEP Position-compare Event Generation Points
The pulse stretcher logic in the position-compare unit generates a programmable position-compare sync pulse
output on the position-compare match. In the event of a new position-compare match while a previous position-
compare pulse is still active, then the pulse stretcher generates a pulse of specified duration from the new
position-compare event as shown in
.
DIR
QPOSCMP
QPOSCNT
PCSOUT (active HIGH)
PCSPW
PCSPW
PCSPW
PCEVNT
Figure 7-14. eQEP Position-compare Sync Output Pulse Stretcher
Enhanced Quadrature Encoder Pulse (eQEP)
SPRUH18I – JANUARY 2011 – REVISED JUNE 2022
TMS320x2806x Microcontrollers
477
Copyright © 2022 Texas Instruments Incorporated
Содержание TMS320 2806 Series
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