EM84502

PS/2 MOUSE CONTROLLER

3

* This specification are subject to be changed without notice.

6.18.1998

2). Set default:

sampling rate: 100 reports/s

non-autospeed

stream mode

2 dot/count

disable

ii). Stream Mode:

The maximum rate of transfer is the programmed sample rate.

Data report is transmitted if

1). switch is pressed

2). movement has been detect

iii). Remote Mode:

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

iv). Wrap Mode:

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

by EM84502.

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 )

C) PS/2 mouse Data Transmission:

i). EM84502 generates the clocking signal when sending data to and receiving data from the system.

ii). The system requests EM84502 receive system data output by forcing the DATA line to an inactive

level and allowing CLK line to go to an active level.

iii). Data transmission frame: