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Rainbow Electronics W90N745CDG User Manual

Page 386

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W90N745CD/W90N745CDG

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6.18.2 Register Description

PS2 Host Controller Command Register (PS2_CMD)

REGISTER

ADDRESS

R/W

DESCRIPTION

RESET VALUE

PS2CMD 0xFFF8_9000

R/W

Command

register

0x0000_0000

31

30

29

28

27

26

25

24

RESERVED

23

22

21

20

19

18

17

16

RESERVED

15

14

13

12

11

10

9

8

RESERVED

TRAP_SHIFT

EnCMD

7

6

5

4

3

2

1

0

PS2CMD

BITS

DESCRIPTIONS

[31:10] RESERVED

-

[9]

TRAP_SHIFT

Trap Shift Key Output to Scan Code Register
If the shift key scan code (0x12 0r 0x59) is received by host,
software can indicate host whether to update to scan code
register or not. No ASCII or SCAN codes will be reported for the
shift keys if this bit is set. In this condition, host will only report the
shift keys at the RX_shift_key bit of Status register and no
interrupt will occur for the shift keys. This is useful for those who
wish to use the ASCII data stream and don’t want to “manually”
filter out the shift key codes. This bit is clear by default.

[8]

EnCMD

Enable write PS2 Host Controller Commands
This bit enables the write function of Host controller comm
device. Set this bit will start the write process of PS2CMD cont
hardware will automatically clear this bit while write pro
finished.

[7:0]

PS2CMD

PS2 Host Controller Commands
This command filed is sent by the Host to the Keyboard. Th
common command would be the setting/resetting of the
Indicators (i.e. the Num lock, Caps Lock & Scroll Lock LEDs).