73S1209F Data Sheet
DS_1209F_004
Keypad Scan Time Register (KSIZE): 0xD5 Å 0x00
This register is not applicable when HWSCEN is not set. Unused row inputs should be connected to
VDD.
Table 69: The KSIZE Register
MSB
LSB
ROWSIZ.2 ROWSIZ.1 ROWSIZ.0 COLSIZ.2 COLSIZ.1 COLSIZ.0
–
–
Bit
Symbol
Function
KSIZE.7
KSIZE.6
KSIZE.5
KSIZE.4
KSIZE.3
KSIZE.2
KSIZE.1
KSIZE.0
–
–
ROWSIZ.2
Defines the number of rows in the keypad. Maximum number is 6 given
ROWSIZ.1 the number of row pins on the package. Allows for a reduced keypad size
for scanning.
ROWSIZ.0
COLSIZ.2
Defines the number of columns in the keypad. Maximum number is 5
COLSIZ.1 given the number of column pins on the package. Allows for a reduced
keypad size for scanning.
COLSIZ.0
Keypad Column LS Scan Order Register (KORDERL): 0xD6 Å 0x00
In registers KORDERL and KORDERH, Column Scan Order(14:0) is grouped into 5 sets of 3 bits each.
Each set determines which column (COL(4:0) pin) to activate by loading the column number into the 3
bits. When in HW_Scan_Enable mode, the hardware will step through the sets from 1Col to 5Col (up to
the number of columns in Colsize) and scan the column defined in the 3 bits. To scan in sequential
order, set a counting pattern with 0 in set 0, and 1 in set 1,and 2 in set 2, and 3 in set 3, and 4 in set 4.
The firmware should update this as part of the interrupt service routine so that the new scan order is
loaded prior to the next key being pressed. For example, to scan COL(0) first, 1Col(2:0) should be
loaded with 000’b. To scan COL(4) fifth, 5Col(2:0) should be loaded with 100’b.
Table 70: The KORDERL Register
MSB
LSB
3COL.1 3COL.0 2COL.2 2COL.1 2COL.0 1COL.2 1COL.1 1COL.0
Bit
Symbol
3COL.1
3COL.0
2COL.2
2COL.1
2COL.0
1COL.2
1COL.1
1COL.0
Function
KORDERL.7
KORDERL.6
KORDERL.5
KORDERL.4
KORDERL.3
KORDERL.2
KORDERL.1
KORDERL.0
Column to scan 3rd (lsb’s).
Column to scan 2nd.
Column to scan 1st.
66
Rev. 1.2
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
