C64 I/O pinout

After searching all over the internet for this I've found the pin out for the C64 serial port. The goal of finding this information: to connect serial port of the C64 to the RS232 serial port on my computer. Here's what I found. Pin, description 1, ? 2, GND 3, ATN 4, CLK 5, DATA 6, RESET The description that I found didn't list pin 1 for anything could this possibly be +5V? If so I could connect this to CTS (I'm trying to keep to the standard). ATN is probably attention which tells what device the computer is going to talk to. CLK is probably a clock signal which could be connected to Receive Clock. Could ATN be connected to DCD on the PC? Also what are the logic levels on the C64 port is it inverted compared to RS232 when it comes to 1 and 0 and what is the voltage on pin five for 1 and 0. Charles