73s1217f68im Maxim Integrated Products, Inc., 73s1217f68im Datasheet - Page 69

• Manufacturer Part Number: 73s1217f68im
• Description: Bus-powered 80515 System-on-chip With Usb, Iso 7816 / Emv, Pinpad And More
• Manufacturer: Maxim Integrated Products, Inc.

Rev. 1.2
No
KORDERL / H Registers:
Column Scan Order
still released ?
Yes
Deboucing
the key(s)
Is (are)
Timer
(*)
1 key
More
than
Figure 14: Keypad Interface Flow Chart
No
Yes
Debouncing Time
KSCAN Register:
column values in KROW and
Download of the key row and
(*) Key release is cheked by looking for a low level on any row.
Keypad Initialization
Keypad Scanning
Keypad Interrupt
KCOL registers
keys have been
Input still = 0 ?
Outputs = 0
All Column
Input = 0 ?
Deboucing
How Many
generation
released ?
detected?
the key(s)
Any Row
Is (are)
Timer
1 key
Row
Any
Yes
(*)
No
0 key
No
KSCAN Register:
Debouncing Time
Keypad Size Definition
Enable Keypad Interrupt
Enable HW Scanning
KSCAN Register:
KSIZE Register:
Scanning Rate
KSTAT Register:
Value of the valid key column
Key Detect Interrupt
Value of the valid key row
KSTAT Register:
KROW Register:
Register written by the hardware
keypad interface
KCOL Register:
Register Used to Control the
hardware keypad interface
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