If anyone wants to try entering a program, here's the "A+B=C" program code. You can use the "cheat sheet" that's "taped" to the front of the Toy to figure out the machine language instructions:
0. LOAD
1. 7 ("A")
2. ADD
3. 8 ("B")
4. STORE
5. 9 ("C")
6. STOP
7. 1 (this is "A")
8. 3 (this is "B")
9. 0 (this is "C", will get overwritten)