Specifications

8.9 Port 80
A header has been provided for monitoring data written to I/O Port 80. The PC BIOS writes
status bytes to Port 80 that indicate a boot progress status and/or highlight any faults found.
Data written to this port can be monitored using a Logic State Analyzer (LSA) or seven segment
hexadecimal displays. See Section A.5.11 for details of the connector used for this port.
After boot-up this port can be used to monitor other status bytes written to Port 80, which can be
useful for debug purposes.
8-20 VP 110/01x
Additional Local I/O Functions