GPIODM-KPLCD Microchip Technology, GPIODM-KPLCD Datasheet - Page 16

• Manufacturer Part Number: GPIODM-KPLCD
• Description: BOARD DEMO LCD GPIO EXP KEYPAD
• Manufacturer: Microchip Technology

Specifications of GPIODM-KPLCD

• Main Purpose: Interface, Front Panel Controller, LCD
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP23008, MCP23S08, MCP23017, MCP23S17, PIC18F4550, MCP1702
• Primary Attributes: (2) 8-Bit and (2) 16-Bit GPIO Expanders, 4x4 Keypad, 2x16 LCD
• Secondary Attributes: Headers for the MCP23x08 and MCP23x17
• Silicon Manufacturer: Microchip
• Core Architecture: PIC
• Core Sub-architecture: PIC18
• Features: SPI And I2C Buses, Keypad And LCD Interface, ICSP Header
• Kit Contents: Board
• Silicon Core Number: PIC18F
• Silicon Family Name: PIC18F4xxx
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• For Use With: MCP23S08/17, MCP23008/17
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Not applicable / Not applicable

GPIO Expander Keypad and LCD Demo Board User’s Guide
DS51636A-page 12
FIGURE 2-4:
time the function is
press from lookup
Swap inputs and
correct the next
Set I/O back to
Read INTCAP
Determine key
Scan_Buttons
default so it is
Read GPIO
outputs
called
table
END
KEYPAD SCAN
One nibble is set to input and
the other nibble is output (to
read the columns) (already
configured before entering
function).
Read INTCAP and place in a
variable.
To read the rows.
Merge with variable
containing INTCAP value.
The result can be looked up
in a table (switch statement)
to determine which key was
pressed.
© 2006 Microchip Technology Inc.