lm8328tmx National Semiconductor Corporation, lm8328tmx Datasheet - Page 13

• Manufacturer Part Number: lm8328tmx
• Description: Mobile I/o Companion Supporting Keyscan, I/o Expansion Pwm, And Access.bus Host Interface
• Manufacturer: National Semiconductor Corporation

11.0 Keyscan Operation
11.1 KEYSCAN INITIALIZATION
11.2 KEYSCAN INITIALIZATION EXAMPLE
Table 6
tialize keyscan:
Register name
KBDBOUNCE
KBDDEDCFG
KBDSETTLE
KBDSIZE
KBDMSK
CLKEN
IOCFG
KBDIC
IOPC0
IOPC1
shows all the LM8328 register configurations to ini-
adress
0xAC
0xAA
0x8A
0x01
0x02
0x03
0x04
0xA7
0x08
0x09
Access
Type
word
word
word
byte
byte
byte
byte
byte
byte
byte
TABLE 6. Keyscan Initialization Example
FIGURE 7. Keyscan Initialization
0xAAAA
0xFC3F
0x5555
Value
0x01
0x80
0x80
0x88
0xF8
0x03
0x03
13
enable keyscan clock
set the keyscan settle time to 12 msec
set the keyscan debounce time to 12 msec
set the keyscan matrix size to 8 rows x 8 columns
configure KPX[7:2] and KPY[7:2] pins as keyboard matrix
write default value to enable all pins as keyboard matrix
configure pull-up resistors for KPX[7:0]
configure pull-down resistors for KPY[7:0]
clear any pending interrupts
enable keyboard interrupts
•
Keypad matrix configuration is 8 rows x 8 columns.
Comment
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