Galil DMC-2X00 - Manual (Page 129)

Command Summary - Homing Operation
command Description
FE ABCD Find Edge Routine. This routine monitors the Home Input
FI ABCD Find Index Routine - This routine monitors the Index Input
HM ABCD Home Routine - This routine combines FE and FI as Described Above
SC ABCD Stop Code
TS ABCD Tell Status of Switches and Inputs
Operand Summary - Homing Operation
Operand Description
_HMa Contains the value of the state of the Home Input
_SCa Contains stop code
_TSa Contains status of switches and inputs
High Speed Position Capture (The Latch Function)
Often it is desirable to capture the position precisely for registration applications. The DMC-2x00
provides a position latch feature. This feature allows the position of the main or auxiliary encoders of
A,B,C or D to be captured when the latch input changes state. This function can be setup such that the
position is captured when the latch input goes high or low. When the latch function is enabled for
active low operation, the position will be captured within 12 microseconds. When the latch function is
enabled for active high operation, the position will be captured within 35 microseconds. Each axis has
one general input associated to the axis for position capture:
Input Function Input Function
IN1 A Axis Latch IN9 E Axis Latch
IN2 B Axis Latch IN10 F Axis Latch
IN3 C Axis Latch IN11 G Axis Latch
IN4 D Axis Latch IN12 H Axis Latch
The DMC-2x00 software commands, AL and RL, are used to arm the latch and report the latched
position. The steps to use the latch are as follows:
1. Give the AL ABCD command to arm the latch for the main encoder and ALSASBSCSD for
the auxiliary encoders.
2. Test to see if the latch has occurred (Input goes low) by using the _AL A or B or C or D
command. Example, V1=_ALA returns the state of the A latch into V1. V1 is 1 if the latch
has not occurred.
3. After the latch has occurred, read the captured position with the RL ABCD command or _RL
ABCD.
NOTE: The latch must be re-armed after each latching event.
DMC-2X00 Chapter 6 Programming Motion y 119