HP dx7300 Technical Reference Manual page 186

Keyboard
C.2.5 Keyboard Commands
Table C-1 lists the commands that the keyboard can send to the system (specifically, to the
8042-type logic).
Command
Key Detection Error/Over/run
BAT Completion
BAT Failure
Echo
Acknowledge (ACK)
Resend
Keyboard ID
Note:
[1] Modes 2 and 3.
[2] Mode 1 only.
C-10
Table C-1.
Keyboard-to-System Commands
Value Description
00h [1] Indicates to the system that a switch closure
couldn't be identified.
FFh [2]
AAh Indicates to the system that the BAT has been
successful.
FCh Indicates failure of the BAT by the keyboard.
EEh Indicates that the Echo command was received by
the keyboard.
FAh Issued by the keyboard as a response to valid
system inputs (except the Echo and Resend
commands).
FEh Issued by the keyboard following an invalid
input.
83ABh Upon receipt of the Read ID command from the
system, the keyboard issues the ACK command
followed by the two IDS bytes.
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