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AN1231

Title	Title AVR242: Multiplexing LED Drive & a 4x4 Keypad on tinyAVR and megaAVR devices
Name	Name AN1231
Date	Date 12/11/2016
Description	Description This Application Note describes a comprehensive system providing a 4 x 4 keypad as input into a real time clock/timer with two outputs and controls external loads and a four digit mulitplexed LED display.

Silicon Products

Title	Product	Title
AT90PWM161	AT90PWM161
AT90USB1286	AT90USB1286
AT90USB646	AT90USB646
AT90USB1287	AT90USB1287
AT90PWM3B	AT90PWM3B
AT90PWM316	AT90PWM316
AT90PWM2B	AT90PWM2B
AT90USB82	AT90USB82
AT90PWM1	AT90PWM1
ATTINY261 Newer Device Available ATTINY261A	ATTINY261	Newer Device Available ATTINY261A
ATtiny84A	ATtiny84A
ATtiny85	ATtiny85
ATtiny44A	ATtiny44A
ATtiny48	ATtiny48
ATtiny24 Newer Device Available ATTINY24A	ATtiny24	Newer Device Available ATTINY24A
ATtiny828	ATtiny828
ATtiny84 Newer Device Available ATTINY84A	ATtiny84	Newer Device Available ATTINY84A
ATtiny861A	ATtiny861A
AT90PWM81	AT90PWM81
AT90USB162	AT90USB162
AT90PWM216	AT90PWM216
ATtiny24A	ATtiny24A
ATtiny2313A	ATtiny2313A
ATtiny26	ATtiny26
AT90USB647	AT90USB647
ATtiny861 Newer Device Available ATTINY861A	ATtiny861	Newer Device Available ATTINY861A
ATTINY10	ATTINY10
ATtiny461A	ATtiny461A
ATTINY5	ATTINY5
ATtiny44 Newer Device Available ATTINY44A	ATtiny44	Newer Device Available ATTINY44A
ATtiny261A	ATtiny261A
ATtiny841	ATtiny841
ATtiny87 ATtiny87	ATtiny87	ATtiny87
ATtiny45	ATtiny45
ATtiny441	ATtiny441
AT90USB82	AT90USB82
AT90USB1286	AT90USB1286
AT90USB1287	AT90USB1287
ATmega164A	ATmega164A
ATmega164P ‎	ATmega164P	‎
ATmega165P Newer Device Available ATMEGA165PA	ATmega165P	Newer Device Available ATMEGA165PA
ATmega644A	ATmega644A
ATmega16U2	ATmega16U2
ATMEGA165PA	ATMEGA165PA
ATmega169P Newer Device Available ATMEGA169PA	ATmega169P	Newer Device Available ATMEGA169PA
ATmega32U2	ATmega32U2
ATmega3290A	ATmega3290A
ATmega3290 Newer Device Available ATMEGA3290A	ATmega3290	Newer Device Available ATMEGA3290A
ATtiny4313	ATtiny4313
AT90USB646	AT90USB646
AT90USB647	AT90USB647
ATmega6450 Newer Device Available ATMEGA6450A	ATmega6450	Newer Device Available ATMEGA6450A
AT90PWM216	AT90PWM216
ATmega64A	ATmega64A
ATmega6490 Newer Device Available ATMEGA6490A	ATmega6490	Newer Device Available ATMEGA6490A
ATmega644 Newer Device Available ATMEGA644A	ATmega644	Newer Device Available ATMEGA644A
ATmega2561	ATmega2561
ATmega16U4	ATmega16U4
AT90PWM316	AT90PWM316
AT90PWM2B	AT90PWM2B
AT90PWM3B	AT90PWM3B
AT90PWM161	AT90PWM161
ATmega164PA	ATmega164PA
ATMEGA162	ATMEGA162
ATmega48PB	ATmega48PB
ATmega48P ‎	ATmega48P	‎
ATmega128	ATmega128
ATmega16M1	ATmega16M1
ATMEGA64M1	ATMEGA64M1
ATmega169A	ATmega169A
ATmega1284P	ATmega1284P
ATmega128A	ATmega128A
ATMEGA3290PA	ATMEGA3290PA
ATmega329PA	ATmega329PA
ATmega329A	ATmega329A
ATmega329P Newer Device Available ATMEGA329PA	ATmega329P	Newer Device Available ATMEGA329PA
ATmega88P ‎	ATmega88P	‎
ATmega8A	ATmega8A
ATmega8 ‎	ATmega8	‎
ATmega168PB	ATmega168PB
ATmega32A	ATmega32A
ATmega32M1	ATmega32M1
ATmega32U4	ATmega32U4
ATmega1284	ATmega1284
ATmega88PB	ATmega88PB
ATmega8U2	ATmega8U2
ATtiny13 Newer Device Available ATTINY13A	ATtiny13	Newer Device Available ATTINY13A
ATmega8515	ATmega8515
ATmega324P ‎	ATmega324P	‎
ATTINY28	ATTINY28
AT90USB162	AT90USB162
AT90PWM81	AT90PWM81
ATmega649P	ATmega649P
ATmega649 Newer Device Available ATMEGA649A	ATmega649	Newer Device Available ATMEGA649A
ATmega640	ATmega640
ATmega64 Newer Device Available ATMEGA64A	ATmega64	Newer Device Available ATMEGA64A
ATmega16A	ATmega16A
AT90PWM1	AT90PWM1
ATmega169PA	ATmega169PA
ATmega16 ‎	ATmega16	‎
ATmega1281	ATmega1281
ATmega3290P Newer Device Available ATMEGA3290PA	ATmega3290P	Newer Device Available ATMEGA3290PA
ATmega329 Newer Device Available ATMEGA329A	ATmega329	Newer Device Available ATMEGA329A
ATtiny43U	ATtiny43U
ATmega8535	ATmega8535
ATtiny102	ATtiny102
ATmega1280	ATmega1280
ATmega88 ‎	ATmega88	‎
ATtiny13A	ATtiny13A
ATtiny25	ATtiny25
ATTINY104	ATTINY104
ATmega48 ‎	ATmega48	‎