73s1210f68im Maxim Integrated Products, Inc., 73s1210f68im Datasheet - Page 63

• Manufacturer Part Number: 73s1210f68im
• Description: Self-contained Smart Card Reader With Pinpad And Power Management
• Manufacturer: Maxim Integrated Products, Inc.

DS_1210F_001
Rev. 1.4
No
KORDERL / H Registers:
Column Scan Order
still released ?
Yes
Deboucing
the key(s)
Is (are)
Timer
(*)
1 key
More
than
Figure 13: Keypad Interface Flow Chart
No
Yes
Debouncing Time
KSCAN Register:
Download of the key row and
column values in KROW and
(*) Key release is cheked by looking for a low level on any row.
Keypad Scanning
Keypad Interrupt
keys have been
KCOL registers
Input still = 0 ?
Initialization
Outputs = 0
All Column
Input = 0 ?
Deboucing
How Many
generation
released ?
detected?
the key(s)
Any Row
Keypad
Is (are)
Timer
1 key
Row
Any
Yes
(*)
No
0 key
No
KSCAN Register:
Debouncing Time
Keypad Size Definition
Enable Keypad Interrupt
KSCAN Register:
Enable HW Scanning
KSIZE Register:
Scanning Rate
KSTAT Register:
Value of the valid key column
Key Detect Interrupt
KSTAT Register:
Value of the valid key row
Register Used to Control the
hardware keypad interface
Register written by the
hardware keypad interface
KROW Register:
KCOL Register:
73S1210F Data Sheet
63