73S1210F Maxim, 73S1210F Datasheet - Page 67

• Manufacturer Part Number: 73S1210F
• Description: The 73S1210F is a versatile and economical CMOS system-on-chip (SoC) device intended for smart card reader applications
• Manufacturer: Maxim

DS_1210F_001
Keypad Column LS Scan Order Register (KORDERL): 0xD6  0x00
In the
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.
Keypad Column MS Scan Order Register (KORDERH): 0xD7  0x00
Rev. 1.4
KORDERH.7
KORDERH.6
KORDERH.5
KORDERH.4
KORDERH.3
KORDERH.2
KORDERH.1
KORDERH.0
KORDERL.7
KORDERL.6
KORDERL.5
KORDERL.4
KORDERL.3
KORDERL.2
KORDERL.1
KORDERL.0
Bit
Bit
KORDERL
MSB
MSB
3COL.1
–
and
Symbol
Symbol
3COL.1
3COL.0
2COL.2
2COL.1
2COL.0
1COL.2
1COL.1
1COL.0
5COL.2
5COL.1
5COL.0
4COL.2
4COL.1
4COL.0
3COL.2
3COL.0
5COL.2
–
KORDERH
2COL.2
5COL.1
Column to scan 3
Column to scan 2
Column to scan 1
Column to scan 5
Column to scan 4
Column to scan 3
registers, Column Scan Order(14:0) is grouped into 5 sets of 3 bits
Table 70: The KORDERH Register
Table 69: The KORDERL Register
2COL.1
5COL.0
rd
nd
st
th
th
rd
.
.
.
.
(lsb’s).
(msb).
2COL.0
4COL.2
Function
Function
1COL.2
4COL.1
1COL.1
4COL.0
73S1210F Data Sheet
1COL.0
3COL.2
LSB
LSB
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