Block Diagram - Intel PXA27 Series Design Manual

18.5.2.2

Block Diagram

See Figure 18-3
interfacing to the PXA27x processor keypad controller. The recommended value for the pull-down
resistors is 100 K Ω
Figure 18-3. Keypad Matrix and Direct Keys Block Diagram (with One Rotary Encoder)
Interrupt
Generator
Keypad
Interface
Registers
Matrix Interface
Keypad Interface Controller
®
Intel PXA27x Processor Family Design Guide
for example of a possible configuration (with of one rotary encoder) when
The voltage reference must be at the same level as VCC_IO.
.
KP_DKIN<0>
KP_DKIN<1>
KP_DKIN<2>
KP_DKIN<3>
Direct
KP_DKIN<4>
Interface
KP_DKIN<5>
KP_DKIN<6>
KP_DKIN<7>
KP_MKOUT<7>
KP_MKOUT<6>
KP_MKOUT<5>
KP_MKOUT<4>
Matrix
KP_MKOUT<3>
Scan
KP_MKOUT<2>
KP_MKOUT<1>
KP_MKOUT<0>
KP_MKIN<0>
KP_MKIN<1>
KP_MKIN<2>
KP_MKIN<3>
Matrix
Sense
KP_MKIN<4>
KP_MKIN<5>
KP_MKIN<6>
KP_MKIN<7>
Keypad Interface
PWR
A
Com
B
Matrix Keypad (3x4)
KEYPAD_003_P2
II:18-9