Do…Loop will infinitely loop the enclosed commands unless Do While or Do Until is used to conditionally terminate the loop. An Exit Do statement can also be used within the DO…LOOP to exit from the loop.

Do
  Commands 
Loop

Dim K As Integer
Do
  K=Adin(0) ' Read AD input from channel 0
  Debug Dec K,Cr
  Delay 1000
Loop

In the above example, the program will loop indefinitely inside Do and Loop. An Exit Do or GOTO statement must be used to get out of the infinite loop.

Do While [Condition]
   Commands
   [Exit Do]
Loop
 
Do
   Commands
   [Exit Do]
Loop While [Condition]

Do…While will loop indefinitely until the While condition is met.

Do Until [Condition]
   Commands
   [Exit Do]
Loop
 
Do
   Commands
   [Exit Do]
Loop Until [Condition]

Do…Until will loop indefinitely until Until condition is met.

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