Agilent Technologies ADNK-6003 Design Manual page 21

Appendix G: PS/2 reporting format
The PS/2 portion of the firmware handles the following requests and commands listed in the table
below.
Hex Code Command
0xFF Reset
0xFE Resend
0xF6 Set Default
0xF5 Disable
0xF4 Enable
0xF3 Set Sampling Rate
0xF2 Read Device Type
0xF0 Set Remote Mode
0xEE Set Wrap Mode
0xEC Reset Wrap Mode
0xEB Read Data
0xEA Set Stream Mode
0xE9 Status Request
0xE8 Set Resolution
0xE7 Set Scaling 2:1
0xE6 Reset Scaling
0xAA Completion Code
0xFA Peripheral ACK
The PS/2 specification calls out the following default mouse report format. Byte 0 is the button
data (1=pressed, 0=released), X and Y optics sign bits, and X and Y overflow bits. Byte 1 is the X
optics data in 2's complement format. Byte 2 has the Y optics data in 2's complement format. At
reset or power-on the standard PS/2 reporting format is enabled.
Bit 7
Byte 0 Y Overflow
Byte 1 X
Byte 2 Y
21
Action
Resets mouse to default states
Resends last data to host
Sets mouse to use default parameters
Disables the mouse
Enables the mouse
Set sampling rate to 10,20,40,60,80,100,200/second
Returns 0x00 to host, indicating the device is a mouse
Sets remote mode so data values are only reported after a read data
command
Set wrap mode until 0xFF or 0xEC is received
Reset to previous mode of operation.
Responds by sending a mouse report packet to host
Sets stream mode
Returns current mode, en/disabled, scaling, button, resolution, and
sampling rate information to the host.
Sets resolution to 1,2,4,8 counts/mm
Sets scaling to 2:1
Resets scaling to 1:1
Command completion code
Sent to acknowledge host requests
X Overflow Y sign X sign
X X X
Y Y Y
Reserved 0 Reserved 0 Right button
X X
Y Y
Bit 0
Left button
X X
Y Y