TI 84 Plus Calculator sPi

[Knight]

Here is my code for creating a sPi program for calculators. I know most people have the same calculator (84, 83, ...), but I just wanted to try this out. My problem is how to run calculation along side the timer function.

Calculate pi:

1->S
0->C

For(A,1,4000,2)
(4/(S*A))->B
B+C->D
D->C
(-1*S)->S
End

Disp "Pi ="
Disp (C+0.0005)    // Error correction due to using a small number. (4000)
Output(1,1,"")

Timer: (Sadly I didn't create this. This goes out to Ticalc.org.)

For(Z,0,9)

For(X,0,59)

For(M,0,99,7)
Output(1,4,Z)
Output(1,5,":")
If X<=9
Then
Output(1,6,0)
Output(1,7,X)
Else
Output(1,6,X)
End

Output(1,8,":")
If M<=9
Then
Output(1,9,0)
Output(1,10,M)
Else
Output(1,9,M)
End

End

End

End

I can't seem to make it so that both run at the same time, and that the timer stops when Pi is found. I bet it is something obvious. (Sorry it has been a while since I have coded anything.)

My goal will be to over clock my calculator.