title: What does the 0x80 port address connect to?
body: <p>When sending a command and reading the data from a certain chip, say the RTC, different documents say that we should wait for some time before reading from the device to make sure the data is available. Many pieces of code make a dummy read from the port <code>0x80</code>. I wanted to know to what device this address location is connected, if any. I am talking with respect to the IA-32 PC architecture.</p>