ak4184 AKM Semiconductor, Inc., ak4184 Datasheet - Page 22

• Manufacturer Part Number: ak4184
• Description: Tsc With Keypad Scanner And Gpio Expander
• Manufacturer: AKM Semiconductor, Inc.

Addr
00H
L
The keypad scanner controller is controlled by the Keypad Control register (Table 12), Keypad Mask register (Table
17 ) and Keypad Column register (Table 19). This register controls the key press interrupt (host scan mode or key-press
scan mode), key-press debounce time interval and hold time. The Keypad Mask register is valid for each key masked
after debounce key scan. The Keypad Column Mask register stops a key scan of a selected key column and is disabled
for the detection of key press.
The KST1 and KST0 bits can be read to determine the state of keypad scanner. The KST1 and KST0 bits and their
descriptions are described in Table 13.
MS0603-E-00
Keypad Control Register (PAGE 1)
NAME
KEY
13:11
Bits
10:8
7:0
15
14
Keypad Debounce Scan initiated by keypad activity (Initial : KST1 bit="1", KST0 bit="0"
KST1
MSB
D15
KEYIRQN
CSN
Name
KST1
KST0
DBN
HLD
DOUT
BUSY
State
Ry
KST0
D14
Description
Key Interrupt enable signal
0 : disable
1 : enable
Key scan initiated by Host/Key
0 : scan starts by key-press
1 : scan starts by Host command
Keypad debounce time interval
Keypad hold time control
Reserved
Figure 13. Keypad Debounce Scan initiated by key activity
KST1
D13
Enable
Detect
(Key interrupt enable, key scan initiated by key touch)
Key
0
0
1
1
DBN[2:0]
Table 11. Keypad Control Register Format
Table 12. Keypad Control Register (Write)
KST0
D12
0
1
0
1
Debounce
Scan
Table 13. KST bit (Read)
D11
Description
No detect
Wait for the command initiated by Host
Keypad Debounce scan is busy.
Data available
HOLD
D10
22
HLD[2:0]
Disable
Detect
Key
KPDATA1,2
D9
Key Detect
then wait
Enable
D8
Debounce
Scan
D7
0
D6
0
HOLD
D5
0
D4
0
D3
0
D2
2007/04
0
[AK4184]
D1
0
LSB
D0
0