Goto

Syntax:

    Goto label

Command Availability:

Available on all microcontrollers.

Explanation:

The Goto command makes the microcontroller jump to the line specified, and continue running the program from there. It is mainly useful for exiting out of loops — if you need to create an infinite loop, use the Do command instead.

Be careful how you use Goto. If used too much, it can make programs very hard to read.

To define a label, put the name of the label alone on a line, followed by a colon (:).

Example:

    'This program will flash the light until the button is pressed
    'off. Notice the label named SWITCH_OFF.

    #chip 16F628A, 4 'Change this line to suit your circuit

    #define BUTTON PORTB.0
    #define LIGHT PORTB.1
    Dir BUTTON In
    Dir LIGHT Out

    Do
    	PulseOut LIGHT, 500 ms
    	If BUTTON = 1 Then Goto SWITCH_OFF          ' <<< the Goto instruction
    	Wait 500 ms
    	If BUTTON = 1 Then Goto SWITCH_OFF
    Loop

    SWITCH_OFF:
    Set LIGHT Off
    'Chip will enter low power mode when program ends

Key line: Goto SWITCH_OFF — jumps straight to the SWITCH_OFF: label the moment the button is pressed, breaking out of the surrounding Do/Loop without waiting for it to finish its current pass.

See Also:

  • Gosub — a jump that can Return back afterwards
  • Labels — defining the target a Goto jumps to, as SWITCH_OFF: does above
  • Do — the preferred way to build an infinite loop instead of looping with Goto
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