allows, you will have to plug in some serial port extension card.
I will in the following limit the scope to what I use: the IA-32
-and derived architectures, but any information about other ones
+and derived architectures, but any information about other ones is
welcome.
# Controlling boot through the serial line
## The other end of the serial line: hardware terminal or emulation
-In any case, you will need a [emergency null modem] to link the
+In any case, you will need a [null modem](http://www.lammertbies.nl/comm/info/RS-232_null_modem.html) to link the
booting host and the terminal (real dumb serial terminal or computer
running an emulator).