Picore and Cron

Hi

I understand that it is possible with Cron to stop or shutdown or reboot the PI at a time I want.
I looked in piCore and found Cron.
But I am not a Linux user so I don't know what to do.

- I don't see how to start Cron in piCore
- I read that the best is to do it manually with HSS. That's no problem. But what is the command for shutdown, stop and reboot.
I understand mnt = mount but that's all.

Can someone tell me what I have to do?

Thanks
Peet