GI

Go Immediate

syntax – GI or GIi

Value: N/A

Units: N/A

Range: N/A

The GI command begins a defined move profile in the same manner as the GO command. Unlike the GO command, where program execution waits until all defined moves have terminated, GI allows program execution to continue when the move has begun. This allows for other program defined processes to take place while an axis is moving, such as independent multi–axis moves, OT commands, and conditional IF blocks.

Examples:

VE1 DI20 GI MS1, “Axis #1 is moving” TD2

In this example, when the DI20 move begins, program execution immediately displays the “Axis #1 is moving” message for 2 seconds. When the TD2 command has executed, the program will terminate; however, axis #1 will continue to move until the DI20 distance is reached. A Stop, Kill, or press of the ESC key will halt a GI based move either inside or outside program execution.

The GI command can cause program execution and moves to be asynchronous. To re–synchronize the end of a GI move with program execution, use the Wait (WT) command, i.e. WT#1 will wait for only axis #1. If a program error occurs during a GI move, the move will stop at the Stop Decel Rate.

VE1 DA100 GI OT1,1 DA0 GI IF1,1 MS1, “All moves done” EB

If a GI move is in progress and an additional move is commanded on the same axis, the additional move will not begin until the GI move has completed.

In this program, one may expect to see the message “All moves done” immediately after the DA100 move begins. In reality, the program will wait at the DA0 GI until the DA100 move has completed before continuing. More simply stated, a move cannot be commanded to begin on an axis that is already moving.

Since GI allows program execution to continue, there can be programming issues when using GI. For example, in the program fragment “LP VE2 DI10 GI OT1 TD1 OT0 EB” shown in Figure 6-2, after the first pass through, the loop command (LP) will wait at the GI command since subsequent GI moves must wait for the present move to finish.

 

 

Figure 6-2

V

 

 

Axis 1

 

 

 

 

T

V

1 Second

1 Second

Output 1

 

 

 

 

T

V

 

 

Axis 1

 

 

 

 

T

V

 

 

Output 1

 

 

 

 

T

The program will operate as shown here.

The program will not operate as shown here.

6-10 Keypad Programming

MN1854

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Baldor mn1854 manual Go Immediate Syntax GI or GIi, Value N/A Units N/A Range N/A