Galil DMC-2X00 user manual Operands, Displaying the value of variables at the terminal, Keyword

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 A-B joystick and assigns it to variables VA and VB to drive the motors at proportional velocities, where

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

Instruction	Interpretation
#JOYSTIK	Label
JG 0,0	Set in Jog mode
BGAB	Begin Motion
#LOOP	Loop
va=@AN[1]*20000	Read joystick A
vb=@AN[2]*20000	Read joystick B
JG va,vb	Jog at variable va,vb
JP#LOOP	Repeat
EN	End

Operands

Operands allow motion or status parameters of the DMC-2x00 to be incorporated into programmable variables and expressions. Most DMC-2x00 commands have an equivalent operand - which are designated by adding an underscore (_) prior to the DMC-2x00 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-2x00 registers. The axis designation is required following the command.

Instruction	Interpretation
posA=_TPA	Assigns value from Tell Position A to the variable posA.
JP #LOOP,_TEA>5	Jump to #LOOP if the position error of A is greater than 5
JP #ERROR,_TC=1	Jump to #ERROR if the error code equals 1.

Operands can be used in an expression and assigned to a programmable variable, but they cannot be assigned a value. For example: _TPA=2 is invalid.

Special Operands (Keywords)

The DMC-2x00 provides a few additional operands which give access to internal variables that are not accessible by standard DMC-2x00 commands.

Keyword

BGn

BN

DA

DL

DM

HMn

LFn

Function

*Returns a 1 if motion on axis ‘n’ is complete, otherwise returns 0. *Returns serial # of the board.

*Returns the number of arrays available

*Returns the number of available labels for programming *Returns the available array memory

*Returns status of Home Switch (equals 0 or 1)

Returns status of Forward Limit switch input of axis ‘n’ (equals 0 or 1)

DMC-2X00 Chapter 7 Application Programming y 101