This counter keeps incrementing each time its Input changes from 0 to 1, until it is reset by setting the Reset input to 1.

if $102 != 0 then 0
else if $100 != 0 && $101 == 0 then $$ + 1

This counter increments up to a preset Limit. When it reaches the limit, it stops counting and sets its Output to 1.

if $103 != 0 then 0
else if $100 != 0 && $101 == 0 && $$ < $102
then $$ + 1

This counter (like the Preset counter) counts up to a preset Limit, but when it reaches the limit it automatically resets and starts counting again.

The Output is 1 for one cycle each time the counter resets.

Register 
Address

Register 
Name

if $100 != 0 && $101 == 0 
then if $$ < $102 then $$ + 1 else 0