You have not solved the problem!!!!!
After you execute CLR S1 the second time you continue with the DELAY-routine and makes a RET to some UNKNOWN place where you continue to execute instructions.
You should follow CLR S1 with a JMP $ or something like it so the program just keeps looping there.
As I mentioned, you can run it in a simulator and find out what it actually does before and after the change.

Anders