Galil DMC-2X00 High Speed Position Capture The Latch Function, Command Summary Homing Operation

Command Summary - Homing Operation

command

FE ABCD

FI ABCD

HM ABCD

SC ABCD

TS ABCD

Description

Find Edge Routine. This routine monitors the Home Input Find Index Routine - This routine monitors the Index Input

Home Routine - This routine combines FE and FI as Described Above Stop Code

Tell Status of Switches and Inputs

Operand Summary - Homing Operation

Operand

_HMa

_SCa

_TSa

Description

Contains the value of the state of the Home Input Contains stop code

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.

74 • Chapter 6 Programming Motion DMC-2X00