Download AP32289 - XMC1000/XMC4000 - Position Interface(POSIF)

Position Interface (POSIF)
AP32289
Quadrature Decoder
3.1.2
Standard Quadrature Mode
Position encoders that work in Standard Quadrature Mode provide two phase signals (Phase A, Phase B),
and encoders with or without an index/top marker signal.

The inputs should be mapped to:
− POSIFx.IN0[D...A]
− POSIFx.IN1[D...A]
− POSIFx.IN2[D...A]

The output pins are POSIFx.OUT0 to POSIFx.OUT5 for Quadrature Clock, Direction, Period Clock, Index
Occurrence, Index (revolution) and Synchronous Start.
− The Quadrature clock gives position up/down count information in conjunction with the Direction
signal.
− The Period clock contains sequences of (AB) or (BA) pulse-pairs for velocity detection.
− The Index Occurrence pin asserts Z-mark/Index (on QDC.ICM conditions), whilst the Index revolution
asserts only once per revolution.
− Synchronous Start output, POSIFx.OUT5, is linked with the module run bit can be used together with
the CAPCOM units for a complete synchronous start, if those CAPCOM units have been preset for
External Events Control (External Start and Extended Start for Start for example, or Flush/Start).
..IN2..
Zero Mark / Index
..IN0..
Phase A
A
Z
..IN1..
B
Phase B
POSIFx
External
Event
Sources
Up to 3 Event
Profiles Select
Edge or Level
Event
Source
Select
H
Function
of Inputs
Select
Target
Timer
Slice
Inputs
CAPCOM Unit CCU4x/-8x
start
stop
capture 0,1
capture 2,3
gate clock
up/down
load Timer
count
override bit
trap
modulate
L
GPIO
ERU1
Event0
true
POSIFx
CAN
CCU4x
2
1
0
Event0
Detect
USIC
false
ADC
CCU8x
3 Events
Control Matrix
SCU
N * Event Controlled Timer Slices CC4y/-8y Functions
Capture
/ Clear
..OUT3..
Count
(Rev.)
..OUT4..
Standard Quadrature
Decoder Mode
Index Signal Occurrence
Index (revolution)
..OUT1..
Direction
Up /
Down
Count
(Pos.)
..OUT0..
Quadrature Clock (position)
+1 +1 +1 +1 +1 +1 +1
-1
-1 -1
-1 -1
-1 -1
..OUT2..
Count
(Per.)
Period Clock (velocity)
(A) (B)
Start/
Flush
-Start
(A) (B)
(A) (B)
(A)
(B) (A)
(B) (A) (B) (A)
..OUT5..
Sync Start
AP32289_POSIF_03.vsd
Figure 11
POSIF in Standard Quadrature mode
Application Note
22
V1.0, 2015-07