UP-X200 (serv.man9). Service Manual - Sharp EPOS Service Manual (repair manual). Page 18

UP-X200

KeyMatrix

– 16 –

The key matrix is connected the PXA255 GPIO. There are a total of 20 keys and except for the power supply key, 19 of those keys are connected to
the matrix. An illustration of connections is shown below. Additionally, because the center trigger, side trigger and [ • ] keys are connected as a sepa-
rate group to the other keys, This enables multiple simultaneous key inputs under specific conditions.

The power supply key is connected to GPIO0 and GPIO22 of the CPU. GPIO0 is the OR of the power supply where the terminal charge stops detec-
tion and a determination of ON is based on the two conditions GPIO0 interruption and the GPIO22 level.
Existence of GPIO0 interruption, GPIO22=L

3

 ON key input

Existence of GPIO0 interruption, GPIO2=L

3

 Supply/stop of charge power supply

A determination is made based on the above conditions.

Terminal names :

Signal names :

DIR:

ACT:

OFF:

Interruption :

Function/description:

WM9712 terminal names

UP-X200 signal names

Input/output direction seen from WM9712

Active polarity

Terminal level when off

Presence/absenceof interruption

Description of signal function

Terminal Name

Signal Name

Normal

OFF

Inter-

ruption

End

Terminal

Function/Description

DIR

ACT.

GPIO1

EAR_IN

O

L

Earphone jack connection detection
0: Connected    1: Not connected

GPIO2/IRQ

AUD_IRQ#

O

L

CODEC interruption request output
0: Interruption factor exists    1: Interruption factor does not exist

GPIO3/

PENDOWN

PEN_IRQ

O

H

Liquid crystal display synchronous signal input
0: Interruption factor exists    1: Interruption factor does not exist

GPIO4/MASK

LCD_SYNC

I

H

LCD synchronized signal input

GPIO5/

SPDIF_OUT

DETECT_MIC#

I

L

Earphone mic detection signal input (Valid only when EAR_IN = "L")
0: Earphone mic    1: Headphone

KEYOUT 0

KEYOUT 1

KEYOUT 2

KEYOUT 3

KEYOUT 4

KEYOUT 5

KEYOUT 6

KEYIN 0

1

2

8

9

Center trigger 

(TRG1)

KEYIN 1

3

7

5

6

Side trigger 

(TRG2)

KEYIN 2

4

4

2

3

KEYIN 3 

CL

 •

1

0

Enter