2561 Register Summary¶

Baud:: Baud Rate
Comp:: Compare
H:: High
In:: Input
L:: Low
Out:: Output
Serial:: Serial Interface
T/C:: Timer/Counter

Ad.	Name	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0	Page
1FF	Reserved
...	Reserved
137	Reserved
136	UDR3	USART3 I/O Data								p218
135	UBRR3H					USART3 Baud H				p222
134	UBRR3L	USART3 Baud L								p222
133	Reserved
132	UCSR3C	UMSEL31	UMSEL30	UPM31	UPM30	USBS3	UCSZ31	UCSZ30	UCPOL3	p235
131	UCSR3B	RXCIE3	TXCIE3	UDRIE3	RXEN3	TXEN3	UCSZ32	RXB83	TXB83	p234
130	UCSR3A	RXC3	TXC3	UDRE3	FE3	DOR3	UPE3	U2X3	MPCM3	p233
12F	Reserved
12E	Reserved
12D	OCR5CH	T/C5 - Out Comp C H								p160
12C	OCR5CL	T/C5 - Out Comp C L								p160
12B	OCR5BH	T/C5 - Out Comp B H								p160
12A	OCR5BL	T/C5 - Out Comp B L								p160
129	OCR5AH	T/C5 - Out Comp A H								p160
128	OCR5AL	T/C5 - Out Comp A L								p160
127	ICR5H	T/C5 - In Capture H								p161
126	ICR5L	T/C5 - In Capture L								p161
125	TCNT5H	T/C5 - Counter H								p158
124	TCNT5L	T/C5 - Counter L								p158
123	Reserved
122	TCCR5C	FOC5A	FOC5B	FOC5C						p157
121	TCCR5B	ICNC5	ICES5		WGM53	WGM52	CS52	CS51	CS50	p156
120	TCCR5A	COM5A1	COM5A0	COM5B1	COM5B0	COM5C1	COM5C0	WGM51	WGM50	p154
11F	Reserved
...	Reserved
10C	Reserved
10B	PORTL	PORTL7	PORTL6	PORTL5	PORTL4	PORTL3	PORTL2	PORTL1	PORTL0	p100
10A	DDRL	DDL7	DDL6	DDL5	DDL4	DDL3	DDL2	DDL1	DDL0	p100
109	PINL	PINL7	PINL6	PINL5	PINL4	PINL3	PINL2	PINL1	PINL0	p100
108	PORTK	PORTK7	PORTK6	PORTK5	PORTK4	PORTK3	PORTK2	PORTK1	PORTK0	p99
107	DDRK	DDK7	DDK6	DDK5	DDK4	DDK3	DDK2	DDK1	DDK0	p99
106	PINK	PINK7	PINK6	PINK5	PINK4	PINK3	PINK2	PINK1	PINK0	p99
105	PORTJ	PORTJ7	PORTJ6	PORTJ5	PORTJ4	PORTJ3	PORTJ2	PORTJ1	PORTJ0	p99
104	DDRJ	DDJ7	DDJ6	DDJ5	DDJ4	DDJ3	DDJ2	DDJ1	DDJ0	p99
103	PINJ	PINJ7	PINJ6	PINJ5	PINJ4	PINJ3	PINJ2	PINJ1	PINJ0	p99
102	PORTH	PORTH7	PORTH6	PORTH5	PORTH4	PORTH3	PORTH2	PORTH1	PORTH0	p98
101	DDRH	DDH7	DDH6	DDH5	DDH4	DDH3	DDH2	DDH1	DDH0	p99
100	PINH	PINH7	PINH6	PINH5	PINH4	PINH3	PINH2	PINH1	PINH0	p99
FF	Reserved
...	Reserved
D7	Reserved
D6	UDR2	USART2 I/O Data								p218
D5	UBRR2H					USART2 Baud H				p222
D4	UBRR2L	USART2 Baud L								p222
D3	Reserved
D2	UCSR2C	UMSEL21	UMSEL20	UPM21	UPM20	USBS2	UCSZ21	UCSZ20	UCPOL2	p235
D1	UCSR2B	RXCIE2	TXCIE2	UDRIE2	RXEN2	TXEN2	UCSZ22	RXB82	TXB82	p234
D0	UCSR2A	RXC2	TXC2	UDRE2	FE2	DOR2	UPE2	U2X2	MPCM2	p233
CF	Reserved
CE	UDR1	USART1 I/O Data								p218
CD	UBRR1H					USART1 Baud H				p222
CC	UBRR1L	USART1 Baud L								p222
CB	Reserved
CA	UCSR1C	UMSEL11	UMSEL10	UPM11	UPM10	USBS1	UCSZ11	UCSZ10	UCPOL1	p235
C9	UCSR1B	RXCIE1	TXCIE1	UDRIE1	RXEN1	TXEN1	UCSZ12	RXB81	TXB81	p234
C8	UCSR1A	RXC1	TXC1	UDRE1	FE1	DOR1	UPE1	U2X1	MPCM1	p233
C7	Reserved
C6	UDR0	USART0 I/O Data								p218
C5	UBRR0H					USART0 Baud H				p222
C4	UBRR0L	USART0 Baud L								p222
C3	Reserved
C2	UCSR0C	UMSEL01	UMSEL00	UPM01	UPM00	USBS0	UCSZ01	UCSZ00	UCPOL0	p235
C1	UCSR0B	RXCIE0	TXCIE0	UDRIE0	RXEN0	TXEN0	UCSZ02	RXB80	TXB80	p234
C0	UCSR0A	RXC0	TXC0	UDRE0	FE0	DOR0	UPE0	U2X0	MPCM0	p234
BF	Reserved
BE	Reserved
BD	TWAMR	TWAM6	TWAM5	TWAM4	TWAM3	TWAM2	TWAM1	TWAM0		p264
BC	TWCR	TWINT	TWEA	TWSTA	TWSTO	TWWC	TWEN		TWIE	p261
BB	TWDR	2-wire Serial Data								p263
BA	TWAR	TWA6	TWA5	TWA4	TWA3	TWA2	TWA1	TWA0	TWGCE	p263
B9	TWSR	TWS7	TWS6	TWS5	TWS4	TWS3		TWPS1	TWPS0	p262
B8	TWBR	2-wire Serial Bit Rate								p261
B7	Reserved
B6	ASSR		EXCLK	AS2	TCN2UB	OCR2AUB	OCR2BUB	TCR2AUB	TCR2BUB	p179
B5	Reserved
B4	OCR2B	T/C2 Out Comp B								p186
B3	OCR2A	T/C2 Out Comp A								p186
B2	TCNT2	T/C2 (8 Bit								p186
B1	TCCR2B	FOC2A	FOC2B			WGM22	CS22	CS21	CS20	p185
B0	TCCR2A	COM2A1	COM2A0	COM2B1	COM2B0			WGM21	WGM20	p186
AF	Reserved
AE	Reserved
AD	OCR4CH	T/C4 - Out Comp C H								p160
AC	OCR4CL	T/C4 - Out Comp C L								p160
AB	OCR4BH	T/C4 - Out Comp B H								p160
AA	OCR4BL	T/C4 - Out Comp B L								p160
A9	OCR4AH	T/C4 - Out Comp A H								p159
A8	OCR4AL	T/C4 - Out Comp A L								p159
A7	ICR4H	T/C4 - In Capture H								p161
A6	ICR4L	T/C4 - In Capture L								p161
A5	TCNT4H	T/C4 - Counter H								p158
A4	TCNT4L	T/C4 - Counter L								p158
A3	Reserved
A2	TCCR4C	FOC4A	FOC4B	FOC4C						p157
A1	TCCR4B	ICNC4	ICES4		WGM43	WGM42	CS42	CS41	CS40	p156
A0	TCCR4A	COM4A1	COM4A0	COM4B1	COM4B0	COM4C1	COM4C0	WGM41	WGM40	p154
9F	Reserved
9E	Reserved
9D	OCR3CH	T/C3 - Out Comp C H								p159
9C	OCR3CL	T/C3 - Out Comp C L								p159
9B	OCR3BH	T/C3 - Out Comp B H								p159
9A	OCR3BL	T/C3 - Out Comp B L								p159
99	OCR3AH	T/C3 - Out Comp A H								p159
98	OCR3AL	T/C3 - Out Comp A L								p159
97	ICR3H	T/C3 - In Capture H								p161
96	ICR3L	T/C3 - In Capture L								p161
95	TCNT3H	T/C3 - Counter H								p158
94	TCNT3L	T/C3 - Counter L								p158
93	Reserved
92	TCCR3C	FOC3A	FOC3B	FOC3C						p157
91	TCCR3B	ICNC3	ICES3		WGM33	WGM32	CS32	CS31	CS30	p156
90	TCCR3A	COM3A1	COM3A0	COM3B1	COM3B0	COM3C1	COM3C0	WGM31	WGM30	p154
8F	Reserved
8E	Reserved
8D	OCR1CH	T/C1 - Out Comp C H								p159
8C	OCR1CL	T/C1 - Out Comp C L								p159
8B	OCR1BH	T/C1 - Out Comp B H								p159
8A	OCR1BL	T/C1 - Out Comp B L								p159
89	OCR1AH	T/C1 - Out Comp A H								p159
88	OCR1AL	T/C1 - Out Comp A L								p159
87	ICR1H	T/C1 - In Capture H								p160
86	ICR1L	T/C1 - In Capture L								p160
85	TCNT1H	T/C1 - Counter H								p158
84	TCNT1L	T/C1 - Counter L								p158
83	Reserved
82	TCCR1C	FOC1A	FOC1B	FOC1C						p157
81	TCCR1B	ICNC1	ICES1		WGM13	WGM12	CS12	CS11	CS10	p156
80	TCCR1A	COM1A1	COM1A0	COM1B1	COM1B0	COM1C1	COM1C0	WGM11	WGM10	p154
7F	DIDR1							AIN1D	AIN0D	p267
7E	DIDR0	ADC7D	ADC6D	ADC5D	ADC4D	ADC3D	ADC2D	ADC1D	ADC0D	p287
7D	DIDR2	ADC15D	ADC14D	ADC13D	ADC12D	ADC11D	ADC10D	ADC9D	ADC8D	p288
7C	ADMUX	REFS1	REFS0	ADLAR	MUX4	MUX3	MUX2	MUX1	MUX0	p281
7B	ADCSRB		ACME			MUX5	ADTS2	ADTS1	ADTS0	p266, 282, 287
7A	ADCSRA	ADEN	ADSC	ADATE	ADIF	ADIE	ADPS2	ADPS1	ADPS0	p285
79	ADCH	ADC Data H byte								p286
78	ADCL	ADC Data L byte								p286
77	Reserved
76	Reserved
75	XMCRB	XMBK					XMM2	XMM1	XMM0	p38
74	XMCRA	SRE	SRL2	SRL1	SRL0	SRW11	SRW10	SRW01	SRW00	p36
73	TIMSK5			ICIE5		OCIE5C	OCIE5B	OCIE5A	TOIE5	p162
72	TIMSK4			ICIE4		OCIE4C	OCIE4B	OCIE4A	TOIE4	p161
71	TIMSK3			ICIE3		OCIE3C	OCIE3B	OCIE3A	TOIE3	p161
70	TIMSK2						OCIE2B	OCIE2A	TOIE2	p188
6F	TIMSK1			ICIE1		OCIE1C	OCIE1B	OCIE1A	TOIE1	p161
6E	TIMSK0						OCIE0B	OCIE0A	TOIE0	p131
6D	PCMSK2	PCINT23	PCINT22	PCINT21	PCINT20	PCINT19	PCINT18	PCINT17	PCINT16	p113
6C	PCMSK1	PCINT15	PCINT14	PCINT13	PCINT12	PCINT11	PCINT10	PCINT9	PCINT8	p113
6B	PCMSK0	PCINT7	PCINT6	PCINT5	PCINT4	PCINT3	PCINT2	PCINT1	PCINT0	p114
6A	EICRB	ISC71	ISC70	ISC61	ISC60	ISC51	ISC50	ISC41	ISC40	p110
69	EICRA	ISC31	ISC30	ISC21	ISC20	ISC11	ISC10	ISC01	ISC00	p110
68	PCICR						PCIE2	PCIE1	PCIE0	p112
67	Reserved
66	OSCCAL	Oscillator Calibration								p48
65	PRR1			PRTIM5	PRTIM4	PRTIM3	PRUSART3	PRUSART2	PRUSART1	p56
64	PRR0	PRTWI	PRTIM2	PRTIM0		PRTIM1	PRSPI	PRUSART0	PRADC	p55
63	Reserved
62	Reserved
61	CLKPR	CLKPCE				CLKPS3	CLKPS2	CLKPS1	CLKPS0	p48
60	WDTCSR	WDIF	WDIE	WDP3	WDCE	WDE	WDP2	WDP1	WDP0	p65
5F	SREG	I	T	H	S	V	N	Z	C	p13
5E	SPH	SP15	SP14	SP13	SP12	SP11	SP10	SP9	SP8	p15
5D	SPL	SP7	SP6	SP5	SP4	SP3	SP2	SP1	SP0	p15
5C	EIND								EIND0	p16
5B	RAMPZ							RAMPZ1	RAMPZ0	p16
5A	Reserved
59	Reserved
58	Reserved
57	SPMCSR	SPMIE	RWWSB	SIGRD	RWWSRE	BLBSET	PGWRT	PGERS	SPMEN	p323
56	Reserved
55	MCUCR	JTD			PUD			IVSEL	IVCE	p64, 108, 96, 301
54	MCUSR				JTRF	WDRF	BORF	EXTRF	PORF	p301
53	SMCR					SM2	SM1	SM0	SE	p50
52	Reserved
51	OCDR	OCDR7	OCDR6	OCDR5	OCDR4	OCDR3	OCDR2	OCDR1	OCDR0	p294
50	ACSR	ACD	ACBG	ACO	ACI	ACIE	ACIC	ACIS1	ACIS0	p266
4F	Reserved
4E	SPDR	SPI Data								p199
4D	SPSR	SPIF	WCOL						SPI2X	p198
4C	SPCR	SPIE	SPE	DORD	MSTR	CPOL	CPHA	SPR1	SPR0	p197
4B	GPIOR2	General Purpose I/O 2								p36
4A	GPIOR1	General Purpose I/O 1								p36
49	Reserved
48	OCR0B	T/C0 Out Comp B								p130
47	OCR0A	T/C0 Out Comp A								p130
46	TCNT0	T/C0 (8 Bit								p130
45	TCCR0B	FOC0A	FOC0B			WGM02	CS02	CS01	CS00	p129
44	TCCR0A	COM0A1	COM0A0	COM0B1	COM0B0			WGM01	WGM00	p126
43	GTCCR	TSM						PSRASY	PSRSYNC	p166, 189
42	EEARH					EEPROM Address H				p34
41	EEARL	EEPROM Address L								p34
40	EEDR	EEPROM Data								p34
3F	EECR			EEPM1	EEPM0	EERIE	EEMPE	EEPE	EERE	p34
3E	GPIOR0	General Purpose I/O 0								p36
3D	EIMSK	INT7	INT6	INT5	INT4	INT3	INT2	INT1	INT0	p111
3C	EIFR	INTF7	INTF6	INTF5	INTF4	INTF3	INTF2	INTF1	INTF0	p112
3B	PCIFR						PCIF2	PCIF1	PCIF0	p113
3A	TIFR5			ICF5		OCF5C	OCF5B	OCF5A	TOV5	p162
39	TIFR4			ICF4		OCF4C	OCF4B	OCF4A	TOV4	p162
38	TIFR3			ICF3		OCF3C	OCF3B	OCF3A	TOV3	p162
37	TIFR2						OCF2B	OCF2A	TOV2	p188
36	TIFR1			ICF1		OCF1C	OCF1B	OCF1A	TOV1	p162
35	TIFR0						OCF0B	OCF0A	TOV0	p131
34	PORTG			PORTG5	PORTG4	PORTG3	PORTG2	PORTG1	PORTG0	p98
33	DDRG			DDG5	DDG4	DDG3	DDG2	DDG1	DDG0	p98
32	PING			PING5	PING4	PING3	PING2	PING1	PING0	p98
31	PORTF	PORTF7	PORTF6	PORTF5	PORTF4	PORTF3	PORTF2	PORTF1	PORTF0	p97
30	DDRF	DDF7	DDF6	DDF5	DDF4	DDF3	DDF2	DDF1	DDF0	p98
2F	PINF	PINF7	PINF6	PINF5	PINF4	PINF3	PINF2	PINF1	PINF0	p98
2E	PORTE	PORTE7	PORTE6	PORTE5	PORTE4	PORTE3	PORTE2	PORTE1	PORTE0	p97
2D	DDRE	DDE7	DDE6	DDE5	DDE4	DDE3	DDE2	DDE1	DDE0	p97
2C	PINE	PINE7	PINE6	PINE5	PINE4	PINE3	PINE2	PINE1	PINE0	p98
2B	PORTD	PORTD7	PORTD6	PORTD5	PORTD4	PORTD3	PORTD2	PORTD1	PORTD0	p97
2A	DDRD	DDD7	DDD6	DDD5	DDD4	DDD3	DDD2	DDD1	DDD0	p97
29	PIND	PIND7	PIND6	PIND5	PIND4	PIND3	PIND2	PIND1	PIND0	p97
28	PORTC	PORTC7	PORTC6	PORTC5	PORTC4	PORTC3	PORTC2	PORTC1	PORTC0	p97
27	DDRC	DDC7	DDC6	DDC5	DDC4	DDC3	DDC2	DDC1	DDC0	p97
26	PINC	PINC7	PINC6	PINC5	PINC4	PINC3	PINC2	PINC1	PINC0	p97
25	PORTB	PORTB7	PORTB6	PORTB5	PORTB4	PORTB3	PORTB2	PORTB1	PORTB0	p96
24	DDRB	DDB7	DDB6	DDB5	DDB4	DDB3	DDB2	DDB1	DDB0	p96
23	PINB	PINB7	PINB6	PINB5	PINB4	PINB3	PINB2	PINB1	PINB0	p96
22	PORTA	PORTA7	PORTA6	PORTA5	PORTA4	PORTA3	PORTA2	PORTA1	PORTA0	p96
21	DDRA	DDA7	DDA6	DDA5	DDA4	DDA3	DDA2	DDA1	DDA0	p96