ADLINK Technology cPCI-8168, User Manual

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66 Operation Theory
Dual Pulse Output Mode (CW/CCW Mode)
In this mode, the waveform of the OUT and DIR pins represent
CW (clockwise) and CCW (counter clockwise) pulse output
respectively. The number of pulses represent distance. The fre-
quency of the pulse represents speed per second. Pulse out-
put from the CW pin makes the motor move in positive
direction, whereas pulse output from the CCW pin makes the
motor move in negative direction. The following diagram
shows the output waveform of positive (+) commands and neg-
ative (-) commands.
Pulse outmode = 4: ( Pulse is normally high )
Pulse outmode = 5: ( Pulse is normally low )
The command pulses are counted by a 28-bit command
counter. The command counter can store a value of total
pulses put out from the controller.
4.3.2 Pulse feedback input interface
The cPCI-8168 provides one a position counter, a 28-bit up/down
counter on each axis for pulse feedback counting. The position
counter counts pulses from the EA and EB signals, which have
plus and minus pins on the connector for differential signal inputs.
It accepts two kinds of pulse types. One is dual pulses input (CW/
CCW mode) and the other is AB phase input. The AB phase input
can be multiplied by 1, 2 or 4. The AB phase multiplied by 4 mode
is the most commonly used in incremental encoder inputs.