Error Messages and Indicators
75
Port 80h POST Codes
During the POST, the BIOS generates diagnostic progress codes (POST codes) to I/O
port 80h. If the POST fails, execution stops and the last POST code generated is left
at port 80h and displayed on the Desktop Board’s seven-segment LED display shown
in Figure 30. This code is useful for determining the point where an e
rror occurred
during the
POST.
Figure 30. POST Code LED Display