EM84510

PS/2 SCROLLING MOUSE CONTROLLER

3

* This specification are subject to be changed without notice.

5.30.2001

FUNCTION DESCRIPTIONS

Legacy PS/2 mouse operating:

(A) Operating mode

There are four operating modes in PS/2 mouse:

a. Reset Mode:

In this mode a self-test is initiated during power-on or by a Reset command. After reset signal, PS/2 mouse

will send:

(a) Completion code AA & ID code 00.

(b) Set default :

sampling rate: 100 reports/s

non-autospeed

stream mode

2 dot/count

disable

b. Stream Mode:

The maximum rate of transfer is the programmed sample rate.

Data report is transmitted if

(a) switch is pressed

(b) movement has been detect

c. Remote Mode:

Data is transmitted only in response to a Read Data command.

d. Wrap Mode:

Any byte of data sent by the system, except hex EC ( Reset wrap mode ) or hex FF ( Reset ), is returned

by EM84510.

B). PS/2 Mouse Data Report:

i).

In stream mode: A data report is sent at the end of a sample interval.

ii). In remote mode: A data report is sent in response to Read Data command.

iii). Data report format:

Byte

Bit

Description

1

0

Left button status; 1 = pressed

1

Right button status; 1 = pressed

2

Middle button status; 1 = pressed

3

Reserve

4

X data sign; 1 = negative

5

Y data sign; 1 = negative

6

X data overflow; 1 = overflow

7

Y data overflow; 1 = overflow

2

0-7

X data ( D0 - D7 )

3

0-7

Y data ( D0 - D7 )