Galil DMC-1700 Digital Inputs, Input Interrupt Function, Example - Start Motion on Switch, 1X80

Example - Turn on output after move

#OUTPUT	Label
PR 2000	Position Command
BG	Begin
AM	After move
SB1	Set Output 1
WT 1000	Wait 1000 msec
CB1	Clear Output 1
EN	End

Digital Inputs

The DMC-1700/1800 has eight digital inputs for controlling motion by local switches. The @IN[n] function returns the logic level of the specified input 1 through 8.

1X80

For the DMC-1750 thru DMC-1780 or DMC-1850 thru DMC-1880, the @IN[n] function is valid for inputs 1 thru 24. For the DMC-17X8, the @IN[n] function is valid for inputs 1 through 80.

For example, a Jump on Condition instruction can be used to execute a sequence if a high condition is noted on an input 3. To halt program execution, the After Input (AI) instruction waits until the specified input has occurred.

Example:

JP #A,@IN[1]=0	Jump to A if input 1 is low
JP #B,@IN[2]=1	Jump to B if input 2 is high
AI 7	Wait until input 7 is high
AI -6	Wait until input 6 is low

Example - Start Motion on Switch

Motor X must turn at 4000 counts/sec when the user flips a panel switch to on. When panel switch is turned to off position, motor X must stop turning.

Solution: Connect panel switch to input 1 of DMC-1700/1800. High on input 1 means switch is in on position.

INSTRUCTION	FUNCTION
#S;JG 4000	Set speed
AI 1;BGX	Begin after input 1 goes high
AI -1;STX	Stop after input 1 goes low
AMX;JP #S	After motion, repeat
EN;

Input Interrupt Function

The DMC-1700/1800 provides an input interrupt function which causes the program to automatically execute the instructions following the #ININT label. This function is enabled using the II m,n,o command. The m specifies the beginning input and n specifies the final input in the range. The parameter o is an interrupt mask. If m and n are

unused, o contains a number with the mask. A 1 designates that input to be enabled for an interrupt, where 20 is bit 1, 21 is bit 2 and so on. For example, II,,5 enables inputs 1 and 3 (20 + 22 = 5).

A low input on any of the specified inputs will cause automatic execution of the #ININT subroutine. The Return from Interrupt (RI) command is used to return from this subroutine to the place in the program where the interrupt

DMC-1700/1800 Chapter 7 Application Programming • 167