0
1
1
0
QA
QB
1
1
0
0
QDECCTL:QBP
Quadrature
decoder
00
01
10
11
iCLK
xCLK
xCLK
xCLK
01
11
10
00
iDIR
xDIR
1
0
QDECCTL:QSRC
2
QFLG:PHE
PHE
QDECCTL:QAP
x1
x2
x1, x2
QDECCTL:XCR
0
1
1
0
QDECCTL:QIP
QDECCTL:IGATE
QCLK
QDIR
QI
1
0
QDECCTL:QSP
0
1
QDECCTL:SPSEL
QDECCTL:SPSEL
1
0
QDECCTL:SOEN
QS
PCSOUT
EQEPxIOE
EQEPxSOE
EQEPxIOUT
EQEPxSOUT
EQEPxSIN
EQEPxIIN
EQEPxBIN
EQEPxAIN
QDECCTL:SWAP
QEPSTS:QDF
EQEPA
EQEPB
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Quadrature Decoder Unit (QDU)
395
SPRUI07–March 2020
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Enhanced Quadrature Encoder Pulse (eQEP)
6.4 Quadrature Decoder Unit (QDU)
Figure 6-5 shows a functional block diagram of the QDU.
Figure 6-5. Functional Block Diagram of Decoder Unit
6.4.1 Position Counter Input Modes
Clock and direction input to the position counter is selected using QDECCTL[QSRC] bits, based on
interface input requirement as follows:
• Quadrature-count mode
• Direction-count mode
• UP-count mode
• DOWN-count mode