Galil DMC-1800, DMC-1700 user manual Operands, Assigning Variable Values to Controller Parameters

(+/-2,147,483,647.9999).

Numeric values can be assigned to programmable variables using the equal sign.

Any valid DMC-1700/1800 function can be used to assign a value to a variable. For example, V1=@ABS[V2] or V2=@IN[1]. Arithmetic operations are also permitted.

To assign a string value, the string must be in quotations. String variables can contain up to six characters which must be in quotation.

Examples:

POSX=_TPX	Assigns returned value from TPX command to variable POSX.
SPEED=5.75	Assigns value 5.75 to variable SPEED
INPUT=@IN[2]	Assigns logical value of input 2 to variable INPUT
V2=V1+V3*V4	Assigns the value of V1 plus V3 times V4 to the variable V2.
VAR=”CAT”	Assign the string, CAT, to VAR

Assigning Variable Values to Controller Parameters

Variable values may be assigned to controller parameters such as GN or PR.

PR V1	Assign V1 to PR command
SP VS*2000	Assign VS*2000 to SP command

Displaying the value of variables at the terminal

Variables may be sent to the screen using the format, variable=. For example, V1= , returns the value of the variable V1.

Example - Using Variables for Joystick

The example below reads the voltage of an X-Y joystick and assigns it to variables VX and VY to drive the motors at proportional velocities, where

10 Volts = 3000 rpm = 200000 c/sec Speed/Analog input = 200000/10 = 20000

#JOYSTIK	Label
JG 0,0	Set in Jog mode
BGXY	Begin Motion
#LOOP	Loop
VX=@AN[1]*20000	Read joystick X
VY=@AN[2]*20000	Read joystick Y
JG VX,VY	Jog at variable VX,VY
JP#LOOP	Repeat
EN	End

Operands

Operands allow motion or status parameters of theDMC-1700/1800 to be incorporated into programmable variables and expressions. Most DMC commands have an equivalent operand - which are designated by adding an underscore (_) prior to the DMC-1700/1800 command. The command reference indicates which commands have an associated operand.

Status commands such as Tell Position return actual values, whereas action commands such as KP or SP return the values in the DMC-1700 or DMC-1800 registers. The axis designation is required following the command.

156 • Chapter 7 Application Programming DMC-1700/1800