NXP Semiconductors MPC5566, Reference Manual

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Enhanced Modular Input/Output Subsystem (eMIOS)
MPC5566 Microcontroller Reference Manual, Rev. 2
17-42 Freescale Semiconductor
When operating with phase_A and phase_B encoder (MODE[6] set), UC n input pin must be connected to
the phase_A signal and UC[n-1] input pin must be connected to the phase_B signal of the quadrature
encoder. EDPOL bit selects the count direction according to the phase difference between phase_A and
phase_B signals.
Figure 17-29 and Figure 17-30 show two unified channels configured to quadrature decode mode for
count and direction encoder and phase_A and phase_B encoders, respectively.
Figure 17-29. Quadrature Decode Mode Example with Count and Direction Encoder
Figure 17-30. Quadrature Decode Mode Example with Phase_A and Phase_B Encoder
Direction
(from UC n )
Count
(from UC[n-1])
EMIOS_CCNTR n
Increment/decrement
A1 write
(value 1)
A1 match A1 match
+1 +1 +1 +1 +1 +1 +1 +1 –1 –1 –1 –1 –1
EMIOS_CCNTR n
Value 1
0x000000
FLAG
set event
Note: Writing EMIOS_CADR n writes to A1.
MODE[6] = 0
EDPOL = 1
Time
Phase A
(from UC n )
Phase B
(from UC[n-1])
EMIOS_CCNTR n
Increment/decrement
A1 write
(value 1) A1 match A1 match
+1
EMIOS_CCNTR n
Value 1
0x000000
FLAG
set event
Note: Writing EMIOS_CADR n writes to A1.
MODE[6] = 1
Time
-1 -1 -1 -1 -1 -1 +1 +1 +1 +1 +1 +1 +1 -1 +1 +1 +1 +1 +1 +1 +1 +1 -1 -1 -1 -1 -1 -1 -1 +1 +1 +1 +1 +1 +1 +1
Value 2
A1 match A1 match A1 match
A1 write
(value 2)