The pork has to be cooked to an internal temperature of minimum 160 degrees to be considered safe, no less. However, it may be a bit pink still which is safe at that temperature. I personally prefer my pork cooked a little longer but, you have to be careful not to dry it up. With some practice you will become an expert!
Also if you have problems finding the temp. another way to check is when the juices run clear, then it's done, just let it sit for a few mins. before cutting into it for a more juicier meat. I'm a cook at a restaurant and I agree with katrinka and honus92 and you might want to get a digital thermometer to help you and some come with a meat temp. chart.