ADLINK Technology PCI-8254, Руководство пользователя

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Motion Control Theory 111
PCI-8254 / PCI-8258
This controller provides multiple auto-home searching process for
different hardware platform which may refer to three mechanical
signals: ORG, EL, and EZ. You may define three homing mode
with these reference signal. User may design required homing
process by any combination of these three signals. Each mode
can have multiple parameters to meet various positioning
requirements. These three homing mode are designed in
accordance with relevant system configurations and have included
commonly available hardware configurations. These three modes
are:
1. ORG signal homing (Home mode = 0) (Home return by ORG sig-
nal)
2. EL signal homing (Home mode = 1)
3. Single EZ signal homing (Home mode = 2)
Homing process and relevant parameters of these three modes
are described below.
4.4.1 OGR Signal Homing - Home Mode = 0
There are three cases for this mode according to its initial position:
Condition A: The initial position is located between MEL and
ORG signals or at MEL signal.
Condition B: Ths initial position is located at ORG signal
Condition C: The initial position is located between PEL and
ORG signals or at PEL signal.
Table and figure below represent homing steps of these three
situations with their speed and position. The three gray area in
figure below represent the ON region of MEL, ORG, and PEL from
left to right respectively. Move forward at the highest speed VM to
search for ORG, decelerate to fully stop when ORG signal is
detected. Then move away from ORG signal in VM speed. Search
ORG again with low speed VO to complete the Home procedure.