Rainbow Electronics W90P710CDG User Manual

Page 514

W90P710CD/W90P710CDG

Publication Release Date: September 19, 2006

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Revision B2

Continued

BITS

DESCRIPTIONS

[8] RX_extend

Receive Extend Byte
A handful of the keys on keyboard are extended keys and thus
require two more scan code. These keys are preceded by an
E0 (hex). This bit indicates software that Host controller
receives extended byte (E0). This bit is read only and will
update when host has received next data byte.

[7:0] RX_SCAN_CODE

PS2 Host Controller Received Data Field
This field stores the original data content transmitted from
device. This filed is valid when RX_IRQ is asserted. Note that
host will not report “Extend” or “Release” scan code to this field
and not generate interrupt if they are received by host, i.e.
0xE0 and 0xF0. The case of the shift key codes will be
determined by the TRAP_SHIFT bit of PS2_CMD register.

PS2 Host Controller RX ASCII Code Register (PS2_ASCII)

REGISTER

ADDRESS

R/W

DESCRIPTION

RESET VALUE

PS2ASCII

0xFFF8_900C

R/W

key pad c RX ASCII Code Register

0x0000_0000

RESERVED

RX_ASCII_CODE

BITS

DESCRIPTIONS

[31:8] RESERVED

[7:0] RX_ASCII_CODE

PS2 Host Controller Received Data Filed
This field stores the ASCII data content transmitted from device.
Therefore, this part translates the scan code into an ASCII
value. It will be read as 0x2E when there is no ASCII code
mapped to the scan code stored in RX_SCAN_CODE register.
This filed is valid when RX_IRQ is asserted.