Technical data

4-36 Fault Isolation
If no output device is present, but a keyboard is, then that keyboard still acts as the
console input device. Similarly, if no input device is present, but a display controller
is, then that display controller still acts as the console output device. If neither an input
device nor an output device is present, the Boot ROM goes ahead and automatically
boots the default operating system as long as no errors are discovered during self test
(see Section 4.9 for more information about the Boot ROM self tests).
Remote Human Interface
Early in the power-up sequence, a search is made for an RS-232 interface set to ‘re
-
mote.’ The search starts at select code 0 and ends at select code 31 or when an RS-232
interface is found that passes self-test. If one is found, it becomes the remote human
interface.
To indicate that a remote human interface has been found at, for example, select code
9, the first line of the display, is
Remote Interface at 9
After this point, the internal display does not change until an operating system is
booted. Any internal or external keyboard, if present, works just as it would if there
were no remote console.
A remote interface requires an 80-column wide terminal with at least 24 lines that ac-
cepts Hewlett-Packard standard terminal escape sequences as listed in the following
table.
Table 4-4. Terminal Escape Sequences
Key Sequence Function
Escape H Escape J
Escape &aDDY
Escape &aDDC
Clear screen and reset cursor.
Move cursor to row DD.
Move cursor to column DD.
4.7.5 Booting Operating Systems over the LAN
LAN interfaces are identified by product number or circuit equivalent, then (LAN)
then the select code, and link address of the interface as follows:
HP98643 (LAN) at 21, 080009000001