STMPE1601 STMicroelectronics, STMPE1601 Datasheet - Page 42

• Manufacturer Part Number: STMPE1601
• Description: 16-bit Enhanced Port Expander With Keypad And Pwm Controller Xpander Logic
• Manufacturer: STMicroelectronics

Keypad controller
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corresponding column input will become 'low' after making contact with the 'low' voltage on
its corresponding row output.
Once the keyscan controller senses a 'low' input on any of the column inputs, the scanning
cycles will then start to determine the exact key that has been pressed. The twelve row
outputs will be driven 'low' one by one during each scanning cycle. While one row is driven
'low', all other rows are in tri-state and pulled up. If there is any column input sensed as 'low'
when a row is driven 'low', the key scan controller will then decode the key coordinates (its
corresponding row number and column number), save the key data into a de-bounce buffer
if available, confirm if it is a valid key press after de-bouncing, and update the key data into
output data FIFO if valid.
Keypad configurations
The keypad controller supports the following types of keys:
●
●
●
Figure 9.
Up to 8 input * 8 output matrix keys
Up to 8 special function keys
Up to 4 dedicated keys
STMPE1601
Maximum configuration
Input 0-7
8*8 (64) Matrix Keys
8 Special Function Keys
0 Dedicated Keys
Special Function Keys
Matrix Keypad
(8*8)
STMPE1601