Features •

Features •
Features
• High-performance, Low-power AVR® 8-bit Microcontroller
• Advanced RISC Architecture
•
•
•
•
•
•
•
– 130 Powerful Instructions – Most Single-clock Cycle Execution
– 32 x 8 General Purpose Working Registers
– Fully Static Operation
– Up to 16 MIPS Throughput at 16 MHz
– On-chip 2-cycle Multiplier
Nonvolatile Program and Data Memories
– 8K Bytes of In-System Self-Programmable Flash
Endurance: 10,000 Write/Erase Cycles
– Optional Boot Code Section with Independent Lock Bits
In-System Programming by On-chip Boot Program
True Read-While-Write Operation
– 512 Bytes EEPROM
Endurance: 100,000 Write/Erase Cycles
– 1K Byte Internal SRAM
– Programming Lock for Software Security
Peripheral Features
– Two 8-bit Timer/Counters with Separate Prescaler, one Compare Mode
– One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture
Mode
– Real Time Counter with Separate Oscillator
– Three PWM Channels
– 8-channel ADC in TQFP and MLF package
Six Channels 10-bit Accuracy
Two Channels 8-bit Accuracy
– 6-channel ADC in PDIP package
Four Channels 10-bit Accuracy
Two Channels 8-bit Accuracy
– Byte-oriented Two-wire Serial Interface
– Programmable Serial USART
– Master/Slave SPI Serial Interface
– Programmable Watchdog Timer with Separate On-chip Oscillator
– On-chip Analog Comparator
Special Microcontroller Features
– Power-on Reset and Programmable Brown-out Detection
– Internal Calibrated RC Oscillator
– External and Internal Interrupt Sources
– Five Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, and
Standby
I/O and Packages
– 23 Programmable I/O Lines
– 28-lead PDIP, 32-lead TQFP, and 32-pad MLF
Operating Voltages
– 2.7 - 5.5V (ATmega8L)
– 4.5 - 5.5V (ATmega8)
Speed Grades
– 0 - 8 MHz (ATmega8L)
– 0 - 16 MHz (ATmega8)
Power Consumption at 4 Mhz, 3V, 25°C
– Active: 3.6 mA
– Idle Mode: 1.0 mA
– Power-down Mode: 0.5 µA
8-bit
with 8K Bytes
In-System
Programmable
Flash
ATmega8
ATmega8L
Preliminary
Summary
Rev. 2486HS–AVR–09/02
Note: This is a summary document. A complete document is
available on our web site at www.atmel.com .
1
Pin Configurations
PDIP
(RESET) PC6
(RXD) PD0
(TXD) PD1
(INT0) PD2
(INT1) PD3
(XCK/T0) PD4
VCC
GND
(XTAL1/TOSC1) PB6
(XTAL2/TOSC2) PB7
(T1) PD5
(AIN0) PD6
(AIN1) PD7
(ICP) PB0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
PC5 (ADC5/SCL)
PC4 (ADC4/SDA)
PC3 (ADC3)
PC2 (ADC2)
PC1 (ADC1)
PC0 (ADC0)
GND
AREF
AVCC
PB5 (SCK)
PB4 (MISO)
PB3 (MOSI/OC2)
PB2 (SS/OC1B)
PB1 (OC1A)
32
31
30
29
28
27
26
25
PD2 (INT0)
PD1 (TXD)
PD0 (RXD)
PC6 (RESET)
PC5 (ADC5/SCL)
PC4 (ADC4/SDA)
PC3 (ADC3)
PC2 (ADC2)
TQFP Top View
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
PC1 (ADC1)
PC0 (ADC0)
ADC7
GND
AREF
ADC6
AVCC
PB5 (SCK)
24
23
22
21
20
19
18
17
PC1 (ADC1)
PC0 (ADC0)
ADC7
GND
AREF
ADC6
AVCC
PB5 (SCK)
(T1) PD5
(AIN0) PD6
(AIN1) PD7
(ICP) PB0
(OC1A) PB1
(SS/OC1B) PB2
(MOSI/OC2) PB3
(MISO) PB4
9
10
11
12
13
14
15
16
(INT1) PD3
(XCK/T0) PD4
GND
VCC
GND
VCC
(XTAL1/TOSC1) PB6
(XTAL2/TOSC2) PB7
32
31
30
29
28
27
26
25
PD2 (INT0)
PD1 (TXD)
PD0 (RXD)
PC6 (RESET)
PC5 (ADC5/SCL)
PC4 (ADC4/SDA)
PC3 (ADC3)
PC2 (ADC2)
MLF Top View
1
2
3
4
5
6
7
8
(T1) PD5
(AIN0) PD6
(AIN1) PD7
(ICP) PB0
(OC1A) PB1
(SS/OC1B) PB2
(MOSI/OC2) PB3
(MISO) PB4
9
10
11
12
13
14
15
16
(INT1) PD3
(XCK/T0) PD4
GND
VCC
GND
VCC
(XTAL1/TOSC1) PB6
(XTAL2/TOSC2) PB7
2
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Overview
The ATmega8 is a low-power CMOS 8-bit microcontroller based on the AVR RISC
architecture. By executing powerful instructions in a single clock cycle, the ATmega8
achieves throughputs approaching 1 MIPS per MHz, allowing the system designer to
optimize power consumption versus processing speed.
Block Diagram
Figure 1. Block Diagram
XTAL1
RESET
PC0 - PC6
PB0 - PB7
VCC
XTAL2
GND
PORTC DRIVERS/BUFFERS
PORTB DRIVERS/BUFFERS
PORTC DIGITAL INTERFACE
PORTB DIGITAL INTERFACE
MUX &
ADC
ADC
INTERFACE
PROGRAM
COUNTER
STACK
POINTER
PROGRAM
FLASH
SRAM
TWI
AGND
AREF
INSTRUCTION
REGISTER
GENERAL
PURPOSE
REGISTERS
TIMERS/
COUNTERS
OSCILLATOR
INTERNAL
OSCILLATOR
WATCHDOG
TIMER
OSCILLATOR
X
INSTRUCTION
DECODER
Y
MCU CTRL.
& TIMING
Z
CONTROL
LINES
ALU
INTERRUPT
UNIT
AVR CPU
STATUS
REGISTER
EEPROM
PROGRAMMING
LOGIC
SPI
USART
+
-
COMP.
INTERFACE
PORTD DIGITAL INTERFACE
PORTD DRIVERS/BUFFERS
PD0 - PD7
3
2486HS–AVR–09/02
The AVR core combines a rich instruction set with 32 general purpose working registers.
All the 32 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing
two independent registers to be accessed in one single instruction executed in one clock
cycle. The resulting architecture is more code efficient while achieving throughputs up to
ten times faster than conventional CISC microcontrollers.
The ATmega8 provides the following features: 8K bytes of In-System Programmable
Flash with Read-While-Write capabilities, 512 bytes of EEPROM, 1K byte of SRAM, 23
general purpose I/O lines, 32 general purpose working registers, three flexible
Timer/Counters with compare modes, internal and external interrupts, a serial programmable USART, a byte oriented Two-wire Serial Interface, a 6-channel ADC (eight
channels in TQFP and MLF packages) where four (six) channels have 10-bit accuracy
and two channels have 8-bit accuracy, a programmable Watchdog Timer with Internal
Oscillator, an SPI serial port, and five software selectable power saving modes. The Idle
mode stops the CPU while allowing the SRAM, Timer/Counters, SPI port, and interrupt
system to continue functioning. The Power-down mode saves the register contents but
freezes the Oscillator, disabling all other chip functions until the next Interrupt or Hardware Reset. In Power-save mode, the asynchronous timer continues to run, allowing the
user to maintain a timer base while the rest of the device is sleeping. The ADC Noise
Reduction mode stops the CPU and all I/O modules except asynchronous timer and
ADC, to minimize switching noise during ADC conversions. In Standby mode, the crystal/resonator Oscillator is running while the rest of the device is sleeping. This allows
very fast start-up combined with low-power consumption.
The device is manufactured using Atmel’s high density non-volatile memory technology.
The Flash Program memory can be reprogrammed In-System through an SPI serial
interface, by a conventional non-volatile memory programmer, or by an On-chip boot
program running on the AVR core. The boot program can use any interface to download
the application program in the Application Flash Memory. Software in the Boot Flash
Section will continue to run while the Application Flash Section is updated, providing
true Read-While-Write operation. By combining an 8-bit RISC CPU with In-System SelfProgrammable Flash on a monolithic chip, the Atmel ATmega8 is a powerful microcontroller that provides a highly-flexible and cost-effective solution to many embedded
control applications.
The ATmega8 AVR is supported with a full suite of program and system development
tools, including C compilers, macro assemblers, program debugger/simulators, In-Circuit Emulators, and evaluation kits.
Disclaimer
4
Typical values contained in this data sheet are based on simulations and characterization of other AVR microcontrollers manufactured on the same process technology. Min
and Max values will be available after the device is characterized.
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Pin Descriptions
VCC
Digital supply voltage.
GND
Ground.
Port B (PB7..PB0)/XTAL1/
XTAL2/TOSC1/TOSC2
Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each
bit). The Port B output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port B pins that are externally pulled low will source
current if the pull-up resistors are activated. The Port B pins are tri-stated when a reset
condition becomes active, even if the clock is not running.
Depending on the clock selection fuse settings, PB6 can be used as input to the inverting Oscillator amplifier and input to the internal clock operating circuit.
Depending on the clock selection fuse settings, PB7 can be used as output from the
inverting Oscillator amplifier.
If the Internal Calibrated RC Oscillator is used as chip clock source, PB7..6 is used as
TOSC2..1 input for the Asynchronous Timer/Counter2 if the AS2 bit in ASSR is set.
The various special features of Port B are elaborated on page 56.
Port C (PC5..PC0)
Port C is an 7-bit bi-directional I/O port with internal pull-up resistors (selected for each
bit). The Port C output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port C pins that are externally pulled low will source
current if the pull-up resistors are activated. The Port C pins are tri-stated when a reset
condition becomes active, even if the clock is not running.
PC6/RESET
If the RSTDISBL Fuse is programmed, PC6 is used as an I/O pin. Note that the electrical characteristics of PC6 differ from those of the other pins of Port C.
If the RSTDISBL Fuse is unprogrammed, PC6 is used as a Reset input. A low level on
this pin for longer than the minimum pulse length will generate a Reset, even if the clock
is not running. The minimum pulse length is given in Table 15 on page 36. Shorter
pulses are not guaranteed to generate a Reset.
The various special features of Port C are elaborated on page 59.
Port D (PD7..PD0)
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each
bit). The Port D output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port D pins that are externally pulled low will source
current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset
condition becomes active, even if the clock is not running.
Port D also serves the functions of various special features of the ATmega8 as listed on
page 61.
RESET
Reset input. A low level on this pin for longer than the minimum pulse length will generate a reset, even if the clock is not running. The minimum pulse length is given in Table
15 on page 36. Shorter pulses are not guaranteed to generate a reset.
XTAL1
Input to the inverting Oscillator amplifier and input to the internal clock operating circuit.
XTAL2
Output from the inverting Oscillator amplifier.
5
2486HS–AVR–09/02
AVCC
AVCC is the supply voltage pin for the A/D Converter, Port C (3..0), and ADC (7..6). It
should be externally connected to VCC, even if the ADC is not used. If the ADC is used,
it should be connected to VCC through a low-pass filter. Note that Port C (5..4) use digital
supply voltage, VCC.
AREF
AREF is the analog reference pin for the A/D Converter.
ADC7..6 (TQFP and MLF
Package Only)
In the TQFP and MLF package, ADC7..6 serve as analog inputs to the A/D converter.
These pins are powered from the analog supply and serve as 10-bit ADC channels.
About Code
Examples
This datasheet contains simple code examples that briefly show how to use various
parts of the device. These code examples assume that the part specific header file is
included before compilation. Be aware that not all C compiler vendors include bit definitions in the header files and interrupt handling in C is compiler dependent. Please
confirm with the C compiler documentation for more details.
6
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Register Summary
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
0x3F (0x5F)
0x3E (0x5E)
Bit 2
Bit 1
Bit 0
Page
SREG
I
T
H
S
V
N
Z
C
9
SPH
–
–
–
–
–
SP10
SP9
SP8
11
0x3D (0x5D)
SPL
SP7
SP6
SP5
SP4
SP3
SP2
SP1
SP0
11
0x3C (0x5C)
Reserved
0x3B (0x5B)
GICR
INT1
INT0
–
–
–
–
IVSEL
IVCE
47, 65
0x3A (0x5A)
GIFR
INTF1
INTF0
–
–
–
–
–
–
66
0x39 (0x59)
TIMSK
OCIE2
TOIE2
TICIE1
OCIE1A
OCIE1B
TOIE1
–
TOIE0
70, 100, 120
0x38 (0x58)
TIFR
OCF2
TOV2
ICF1
OCF1A
OCF1B
TOV1
–
TOV0
71, 101, 120
0x37 (0x57)
SPMCR
SPMIE
RWWSB
–
RWWSRE
BLBSET
PGWRT
PGERS
SPMEN
208
0x36 (0x56)
TWCR
TWINT
TWEA
TWSTA
TWSTO
TWWC
TWEN
–
TWIE
167
0x35 (0x55)
MCUCR
SE
SM2
SM1
SM0
ISC11
ISC10
ISC01
ISC00
31, 64
0x34 (0x54)
MCUCSR
–
–
–
–
WDRF
BORF
EXTRF
PORF
39
0x33 (0x53)
TCCR0
–
–
–
–
–
CS02
CS01
CS00
70
0x32 (0x52)
TCNT0
Timer/Counter0 (8 Bits)
70
0x31 (0x51)
OSCCAL
Oscillator Calibration Register
29
0x30 (0x50)
SFIOR
–
–
–
ADHSM
ACME
PUD
PSR2
PSR10
0x2F (0x4F)
TCCR1A
COM1A1
COM1A0
COM1B1
COM1B0
FOC1A
FOC1B
WGM11
WGM10
95
0x2E (0x4E)
TCCR1B
ICNC1
ICES1
–
WGM13
WGM12
CS12
CS11
CS10
98
0x2D (0x4D)
TCNT1H
Timer/Counter1 – Counter Register High Byte
99
0x2C (0x4C)
TCNT1L
0x2B (0x4B)
OCR1AH
Timer/Counter1 – Counter Register Low Byte
Timer/Counter1 – Output Compare Register A High Byte
99
56, 73, 121, 188
99
0x2A (0x4A)
OCR1AL
Timer/Counter1 – Output Compare Register A Low Byte
99
0x29 (0x49)
OCR1BH
Timer/Counter1 – Output Compare Register B High Byte
99
0x28 (0x48)
OCR1BL
Timer/Counter1 – Output Compare Register B Low Byte
99
0x27 (0x47)
ICR1H
Timer/Counter1 – Input Capture Register High Byte
100
0x26 (0x46)
ICR1L
0x25 (0x45)
TCCR2
Timer/Counter1 – Input Capture Register Low Byte
0x24 (0x44)
TCNT2
Timer/Counter2 (8 Bits)
117
0x23 (0x43)
OCR2
Timer/Counter2 Output Compare Register
117
FOC2
WGM20
COM21
COM20
WGM21
100
CS22
CS21
CS20
0x22 (0x42)
ASSR
–
–
–
–
AS2
TCN2UB
OCR2UB
TCR2UB
0x21 (0x41)
WDTCR
–
–
–
WDCE
WDE
WDP2
WDP1
WDP0
UBRRH
URSEL
–
–
–
0x20(1) (0x40)(1)
UBRR[11:8]
115
117
41
154
UCSRC
URSEL
UMSEL
UPM1
UPM0
USBS
UCSZ1
UCSZ0
UCPOL
0x1F (0x3F)
EEARH
–
–
–
–
–
–
–
EEAR8
18
0x1E (0x3E)
EEARL
EEAR7
EEAR6
EEAR5
EEAR4
EEAR3
EEAR2
EEAR1
EEAR0
18
0x1D (0x3D)
EEDR
0x1C (0x3C)
EECR
–
–
–
–
EERIE
EEMWE
EEWE
EERE
18
0x1B (0x3B)
Reserved
0x1A (0x3A)
Reserved
0x19 (0x39)
Reserved
0x18 (0x38)
PORTB
PORTB7
PORTB6
PORTB5
PORTB4
PORTB3
PORTB2
PORTB1
PORTB0
63
0x17 (0x37)
DDRB
DDB7
DDB6
DDB5
DDB4
DDB3
DDB2
DDB1
DDB0
63
0x16 (0x36)
PINB
PINB7
PINB6
PINB5
PINB4
PINB3
PINB2
PINB1
PINB0
63
0x15 (0x35)
PORTC
–
PORTC6
PORTC5
PORTC4
PORTC3
PORTC2
PORTC1
PORTC0
63
0x14 (0x34)
DDRC
–
DDC6
DDC5
DDC4
DDC3
DDC2
DDC1
DDC0
63
0x13 (0x33)
PINC
–
PINC6
PINC5
PINC4
PINC3
PINC2
PINC1
PINC0
63
0x12 (0x32)
PORTD
PORTD7
PORTD6
PORTD5
PORTD4
PORTD3
PORTD2
PORTD1
PORTD0
63
0x11 (0x31)
DDRD
DDD7
DDD6
DDD5
DDD4
DDD3
DDD2
DDD1
DDD0
63
0x10 (0x30)
PIND
PIND7
PIND6
PIND5
PIND4
PIND3
PIND2
PIND1
PIND0
0x0F (0x2F)
SPDR
EEPROM Data Register
152
18
SPI Data Register
63
128
0x0E (0x2E)
SPSR
SPIF
WCOL
–
–
–
–
–
SPI2X
128
0x0D (0x2D)
SPCR
SPIE
SPE
DORD
MSTR
CPOL
CPHA
SPR1
SPR0
126
0x0C (0x2C)
UDR
0x0B (0x2B)
UCSRA
RXC
TXC
UDRE
USART I/O Data Register
FE
DOR
PE
U2X
MPCM
149
150
0x0A (0x2A)
UCSRB
RXCIE
TXCIE
UDRIE
RXEN
TXEN
UCSZ2
RXB8
TXB8
151
0x09 (0x29)
UBRRL
0x08 (0x28)
ACSR
ACD
ACBG
ACO
ACIC
ACIS1
ACIS0
189
0x07 (0x27)
ADMUX
REFS1
REFS0
0x06 (0x26)
ADCSRA
ADEN
ADSC
0x05 (0x25)
ADCH
ADC Data Register High Byte
203
0x04 (0x24)
ADCL
ADC Data Register Low Byte
203
0x03 (0x23)
TWDR
0x02 (0x22)
TWAR
USART Baud Rate Register Low Byte
154
ACI
ACIE
ADLAR
–
MUX3
MUX2
MUX1
MUX0
200
ADFR
ADIF
ADIE
ADPS2
ADPS1
ADPS0
202
Two-wire Serial Interface Data Register
TWA6
TWA5
TWA4
TWA3
TWA2
169
TWA1
TWA0
TWGCE
169
7
2486HS–AVR–09/02
Register Summary (Continued)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Page
0x01 (0x21)
TWSR
TWS7
TWS6
TWS5
TWS4
TWS3
–
TWPS1
TWPS0
168
0x00 (0x20)
TWBR
Notes:
8
Two-wire Serial Interface Bit Rate Register
167
1. Refer to the USART description for details on how to access UBRRH and UCSRC.
2. For compatibility with future devices, reserved bits should be written to zero if accessed. Reserved I/O memory addresses
should never be written.
3. Some of the Status Flags are cleared by writing a logical one to them. Note that the CBI and SBI instructions will operate on
all bits in the I/O Register, writing a one back into any flag read as set, thus clearing the flag. The CBI and SBI instructions
work with registers 0x00 to 0x1F only.
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Instruction Set Summary
Mnemonics
Operands
Description
Operation
Flags
#Clocks
ARITHMETIC AND LOGIC INSTRUCTIONS
ADD
Rd, Rr
Add two Registers
Rd ← Rd + Rr
Z,C,N,V,H
1
ADC
Rd, Rr
Add with Carry two Registers
Rd ← Rd + Rr + C
Z,C,N,V,H
1
ADIW
Rdl,K
Add Immediate to Word
Rdh:Rdl ← Rdh:Rdl + K
Z,C,N,V,S
2
SUB
Rd, Rr
Subtract two Registers
Rd ← Rd - Rr
Z,C,N,V,H
1
SUBI
Rd, K
Subtract Constant from Register
Rd ← Rd - K
Z,C,N,V,H
1
SBC
Rd, Rr
Subtract with Carry two Registers
Rd ← Rd - Rr - C
Z,C,N,V,H
1
SBCI
Rd, K
Subtract with Carry Constant from Reg.
Rd ← Rd - K - C
Z,C,N,V,H
1
SBIW
Rdl,K
Subtract Immediate from Word
Rdh:Rdl ← Rdh:Rdl - K
Z,C,N,V,S
2
AND
Rd, Rr
Logical AND Registers
Rd ← Rd • Rr
Z,N,V
1
ANDI
Rd, K
Logical AND Register and Constant
Rd ← Rd • K
Z,N,V
1
OR
Rd, Rr
Logical OR Registers
Rd ← Rd v Rr
Z,N,V
1
ORI
Rd, K
Logical OR Register and Constant
Rd ← Rd v K
Z,N,V
1
EOR
Rd, Rr
Exclusive OR Registers
Rd ← Rd ⊕ Rr
Z,N,V
1
COM
Rd
One’s Complement
Rd ← 0xFF − Rd
Z,C,N,V
1
NEG
Rd
Two’s Complement
Rd ← 0x00 − Rd
Z,C,N,V,H
1
SBR
Rd,K
Set Bit(s) in Register
Rd ← Rd v K
Z,N,V
1
CBR
Rd,K
Clear Bit(s) in Register
Rd ← Rd • (0xFF - K)
Z,N,V
1
INC
Rd
Increment
Rd ← Rd + 1
Z,N,V
1
DEC
Rd
Decrement
Rd ← Rd − 1
Z,N,V
1
TST
Rd
Test for Zero or Minus
Rd ← Rd • Rd
Z,N,V
1
CLR
Rd
Clear Register
Rd ← Rd ⊕ Rd
Z,N,V
1
SER
Rd
Set Register
Rd ← 0xFF
None
1
MUL
Rd, Rr
Multiply Unsigned
R1:R0 ← Rd x Rr
Z,C
2
MULS
Rd, Rr
Multiply Signed
R1:R0 ← Rd x Rr
Z,C
2
MULSU
Rd, Rr
Multiply Signed with Unsigned
R1:R0 ← Rd x Rr
Z,C
2
FMUL
Rd, Rr
Fractional Multiply Unsigned
R1:R0 ← (Rd x Rr) <<
Z,C
2
FMULS
Rd, Rr
Fractional Multiply Signed
Z,C
2
FMULSU
Rd, Rr
Fractional Multiply Signed with Unsigned
Z,C
2
1
R1:R0 ← (Rd x Rr) << 1
R1:R0 ← (Rd x Rr) << 1
BRANCH INSTRUCTIONS
RJMP
k
IJMP
Relative Jump
PC ← PC + k + 1
None
2
Indirect Jump to (Z)
PC ← Z
None
2
3
JMP
k
Direct Jump
PC ← k
None
RCALL
k
Relative Subroutine Call
PC ← PC + k + 1
None
3
Indirect Call to (Z)
PC ← Z
None
3
Direct Subroutine Call
PC ← k
None
4
Subroutine Return
PC ← STACK
None
4
ICALL
CALL
k
RET
Interrupt Return
PC ← STACK
I
Compare, Skip if Equal
if (Rd = Rr) PC ← PC + 2 or 3
None
Rd,Rr
Compare
Rd − Rr
Z, N,V,C,H
1
Rd,Rr
Compare with Carry
Rd − Rr − C
Z, N,V,C,H
1
CPI
Rd,K
Compare Register with Immediate
Rd − K
Z, N,V,C,H
SBRC
Rr, b
Skip if Bit in Register Cleared
if (Rr(b)=0) PC ← PC + 2 or 3
None
1/2/3
1/2/3
RETI
CPSE
Rd,Rr
CP
CPC
4
1/2/3
1
SBRS
Rr, b
Skip if Bit in Register is Set
if (Rr(b)=1) PC ← PC + 2 or 3
None
SBIC
P, b
Skip if Bit in I/O Register Cleared
if (P(b)=0) PC ← PC + 2 or 3
None
1/2/3
SBIS
P, b
Skip if Bit in I/O Register is Set
if (P(b)=1) PC ← PC + 2 or 3
None
1/2/3
BRBS
s, k
Branch if Status Flag Set
if (SREG(s) = 1) then PC←PC+k + 1
None
1/2
BRBC
s, k
Branch if Status Flag Cleared
if (SREG(s) = 0) then PC←PC+k + 1
None
1/2
BREQ
k
Branch if Equal
if (Z = 1) then PC ← PC + k + 1
None
1/2
BRNE
k
Branch if Not Equal
if (Z = 0) then PC ← PC + k + 1
None
1/2
BRCS
k
Branch if Carry Set
if (C = 1) then PC ← PC + k + 1
None
1/2
BRCC
k
Branch if Carry Cleared
if (C = 0) then PC ← PC + k + 1
None
1/2
BRSH
k
Branch if Same or Higher
if (C = 0) then PC ← PC + k + 1
None
1/2
BRLO
k
Branch if Lower
if (C = 1) then PC ← PC + k + 1
None
1/2
BRMI
k
Branch if Minus
if (N = 1) then PC ← PC + k + 1
None
1/2
BRPL
k
Branch if Plus
if (N = 0) then PC ← PC + k + 1
None
1/2
BRGE
k
Branch if Greater or Equal, Signed
if (N ⊕ V= 0) then PC ← PC + k + 1
None
1/2
BRLT
k
Branch if Less Than Zero, Signed
if (N ⊕ V= 1) then PC ← PC + k + 1
None
1/2
BRHS
k
Branch if Half Carry Flag Set
if (H = 1) then PC ← PC + k + 1
None
1/2
BRHC
k
Branch if Half Carry Flag Cleared
if (H = 0) then PC ← PC + k + 1
None
1/2
BRTS
k
Branch if T Flag Set
if (T = 1) then PC ← PC + k + 1
None
1/2
BRTC
k
Branch if T Flag Cleared
if (T = 0) then PC ← PC + k + 1
None
1/2
BRVS
k
Branch if Overflow Flag is Set
if (V = 1) then PC ← PC + k + 1
None
1/2
BRVC
k
Branch if Overflow Flag is Cleared
if (V = 0) then PC ← PC + k + 1
None
1/2
9
2486HS–AVR–09/02
Instruction Set Summary (Continued)
Mnemonics
Operands
Description
Operation
Flags
#Clocks
BRIE
k
Branch if Interrupt Enabled
if ( I = 1) then PC ← PC + k + 1
None
1/2
BRID
k
Branch if Interrupt Disabled
if ( I = 0) then PC ← PC + k + 1
None
1/2
DATA TRANSFER INSTRUCTIONS
MOV
Rd, Rr
Move Between Registers
Rd ← Rr
None
1
MOVW
Rd, Rr
Copy Register Word
Rd+1:Rd ← Rr+1:Rr
None
1
LDI
Rd, K
Load Immediate
Rd ← K
None
1
LD
Rd, X
Load Indirect
Rd ← (X)
None
2
LD
Rd, X+
Load Indirect and Post-Inc.
Rd ← (X), X ← X + 1
None
2
LD
Rd, - X
Load Indirect and Pre-Dec.
X ← X - 1, Rd ← (X)
None
2
LD
Rd, Y
Load Indirect
Rd ← (Y)
None
2
LD
Rd, Y+
Load Indirect and Post-Inc.
Rd ← (Y), Y ← Y + 1
None
2
LD
Rd, - Y
Load Indirect and Pre-Dec.
Y ← Y - 1, Rd ← (Y)
None
2
LDD
Rd,Y+q
Load Indirect with Displacement
Rd ← (Y + q)
None
2
LD
Rd, Z
Load Indirect
Rd ← (Z)
None
2
LD
Rd, Z+
Load Indirect and Post-Inc.
Rd ← (Z), Z ← Z+1
None
2
LD
Rd, -Z
Load Indirect and Pre-Dec.
Z ← Z - 1, Rd ← (Z)
None
2
LDD
Rd, Z+q
Load Indirect with Displacement
Rd ← (Z + q)
None
2
LDS
Rd, k
Load Direct from SRAM
Rd ← (k)
None
2
ST
X, Rr
Store Indirect
(X) ← Rr
None
2
ST
X+, Rr
Store Indirect and Post-Inc.
(X) ← Rr, X ← X + 1
None
2
ST
- X, Rr
Store Indirect and Pre-Dec.
X ← X - 1, (X) ← Rr
None
2
ST
Y, Rr
Store Indirect
(Y) ← Rr
None
2
ST
Y+, Rr
Store Indirect and Post-Inc.
(Y) ← Rr, Y ← Y + 1
None
2
ST
- Y, Rr
Store Indirect and Pre-Dec.
Y ← Y - 1, (Y) ← Rr
None
2
STD
Y+q,Rr
Store Indirect with Displacement
(Y + q) ← Rr
None
2
ST
Z, Rr
Store Indirect
(Z) ← Rr
None
2
ST
Z+, Rr
Store Indirect and Post-Inc.
(Z) ← Rr, Z ← Z + 1
None
2
ST
-Z, Rr
Store Indirect and Pre-Dec.
Z ← Z - 1, (Z) ← Rr
None
2
2
STD
Z+q,Rr
Store Indirect with Displacement
(Z + q) ← Rr
None
STS
k, Rr
Store Direct to SRAM
(k) ← Rr
None
2
Load Program Memory
R0 ← (Z)
None
3
LPM
LPM
Rd, Z
Load Program Memory
Rd ← (Z)
None
3
LPM
Rd, Z+
Load Program Memory and Post-Inc
Rd ← (Z), Z ← Z+1
None
3
Store Program Memory
(Z) ← R1:R0
None
-
SPM
IN
Rd, P
In Port
Rd ← P
None
1
OUT
P, Rr
Out Port
P ← Rr
None
1
PUSH
Rr
Push Register on Stack
STACK ← Rr
None
2
POP
Rd
Pop Register from Stack
Rd ← STACK
None
2
BIT AND BIT-TEST INSTRUCTIONS
SBI
P,b
Set Bit in I/O Register
I/O(P,b) ← 1
None
2
CBI
P,b
Clear Bit in I/O Register
I/O(P,b) ← 0
None
2
LSL
Rd
Logical Shift Left
Rd(n+1) ← Rd(n), Rd(0) ← 0
Z,C,N,V
1
LSR
Rd
Logical Shift Right
Rd(n) ← Rd(n+1), Rd(7) ← 0
Z,C,N,V
1
ROL
Rd
Rotate Left Through Carry
Rd(0)←C,Rd(n+1)← Rd(n),C←Rd(7)
Z,C,N,V
1
ROR
Rd
Rotate Right Through Carry
Rd(7)←C,Rd(n)← Rd(n+1),C←Rd(0)
Z,C,N,V
1
ASR
Rd
Arithmetic Shift Right
Rd(n) ← Rd(n+1), n=0..6
Z,C,N,V
1
SWAP
Rd
Swap Nibbles
Rd(3..0)←Rd(7..4),Rd(7..4)←Rd(3..0)
None
1
BSET
s
Flag Set
SREG(s) ← 1
SREG(s)
1
BCLR
s
Flag Clear
SREG(s) ← 0
SREG(s)
1
BST
Rr, b
Bit Store from Register to T
T ← Rr(b)
T
1
BLD
Rd, b
Bit load from T to Register
Rd(b) ← T
None
1
SEC
Set Carry
C←1
C
1
CLC
Clear Carry
C←0
C
1
SEN
Set Negative Flag
N←1
N
1
CLN
Clear Negative Flag
N←0
N
1
SEZ
Set Zero Flag
Z←1
Z
1
CLZ
Clear Zero Flag
Z←0
Z
1
SEI
Global Interrupt Enable
I←1
I
1
CLI
Global Interrupt Disable
I←0
I
1
SES
Set Signed Test Flag
S←1
S
1
CLS
Clear Signed Test Flag
S←0
S
1
SEV
Set Twos Complement Overflow.
V←1
V
1
CLV
Clear Twos Complement Overflow
V←0
V
1
SET
Set T in SREG
T←1
T
1
10
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Instruction Set Summary (Continued)
Mnemonics
Operands
Description
Operation
Flags
#Clocks
CLT
Clear T in SREG
T←0
T
1
SEH
Set Half Carry Flag in SREG
H←1
H
1
CLH
Clear Half Carry Flag in SREG
H←0
H
1
MCU CONTROL INSTRUCTIONS
NOP
SLEEP
WDR
No Operation
Sleep
Watchdog Reset
(see specific descr. for Sleep function)
(see specific descr. for WDR/timer)
None
None
None
1
1
1
11
2486HS–AVR–09/02
Ordering Information
Speed (MHz)
Power Supply
Ordering Code
Package
Operation Range
8
2.7 - 5.5
ATmega8L-8AC
ATmega8L-8PC
ATmega8L-8MC
32A
28P3
32M1-A
Commercial
(0°C to 70°C)
ATmega8L-8AI
ATmega8L-8PI
ATmega8L-8MI
32A
28P3
32M1-A
Industrial
(-40°C to 85°C)
ATmega8-16AC
ATmega8-16PC
ATmega8-16MC
32A
28P3
32M1-A
Commercial
(0°C to 70°C)
ATmega8-16AI
ATmega8-16PI
ATmega8-16MI
32A
28P3
32M1-A
Industrial
(-40°C to 85°C)
16
Note:
4.5 - 5.5
This device can also be supplied in wafer form. Please contact your local Atmel sales office for detailed ordering information and
minimum quantities.
Package Type
32A
32-lead, Thin (1.0 mm) Plastic Quad Flat Package (TQFP)
28P3
28-lead, 0.300” Wide, Plastic Dual Inline Package (PDIP)
32M1-A
32-pad, 5 x 5 x 1.0 body, Lead Pitch 0.50 mm Micro Lead Frame Package (MLF)
12
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Packaging Information
32A
32-lead, Thin (1.0mm) Plastic Quad Flatpack
(TQFP), 7x7mm body, 2.0mm footprint, 0.8mm pitch.
Dimensions in Millimeters and (Inches)*
JEDEC STADARD MS-026 ABA
9.25 (0.364)
8.75 (0.344)
PIN 1 ID
0.45 (0.018)
0.30 (0.012)
PIN 1
9.25 (0.364)
8.75 (0.344)
0.80 (0.0315) BSC
7.10 (0.280)
6.90 (0.272)
SQ
1.20 (0.047) MAX
0.20 (0.008)
0.09 (0.004)
0º~7º
0.75 (0.030)
0.45 (0.018)
0.15 (0.006)
0.05 (0.002)
*Controlling dimensions: Millimeters
13
2486HS–AVR–09/02
28P3
28-lead, Plastic Dual Inline
Package (PDIP), 0.300" Wide, (0.288" body width)
Dimensions in Millimeters and (Inches)*
34.80(1.370)
34.54(1.360)
7.49(0.295)
7.11(0.280)
4.57(0.180)MAX
3.56(0.140)
3.05(0.120)
0.56(0.022)
2.54(0.100)BSC
1.65(0.065)
0.38(0.015)
1.27(0.050)
8.26(0.325)
7.62(0.300)
0º~ 15º REF
0.38(0.015)
10.20(0.400)MAX
*Controlling dimension: Inches
REV. A
14
04/11/2001
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
32M1-A
D
D1
PIN #1 ID
1
2
3
0
E1
E
TOP VIEW
A3
A2
P
A1
D2
A
0.08 C
PIN 1 ID
SIDE VIEW
1
2
3
P
COMMON DIMENSIONS
(*Unit of Measure = mm)
E2
SYMBOL
MIN
NOM
MAX
A
0.80
0.90
1.00
A1
0.00
0.02
0.05
A2
-
0.65
1.00
A3
b
e
b
L
BOTTOM VIEW
NOTE 1. JEDEC STANDARD MO-220, Fig 2 (Anvil Singulation), VHHD-2
0.20 REF
0.18
D
0.30
4.75 BSC
1.25
-
E
5.00 BSC
E1
4.75 BSC
E2
1.25
e
R
0.23
5.00 BSC
D1
D2
NOTE
-
3.25
3.25
0.50 BSC
L
0.30
0.40
0.50
P
-
-
0.60
0
-
-
12º
06/27/01
DRAWING NO.
2325 Orchard Parkway TITLE
32M1-A, 32-pad, 5x5x1.0mm body, Lead Pitch 0.50mm
San Jose, CA 95131
32M1-A
Mirco Lead Frame package (MLF)
REV
A
15
2486HS–AVR–09/02
Data Sheet Change
Log for ATmega8
This document contains a log on the changes made to the data sheet for ATmega8.
Changes from Rev.
2486B-12/01 to Rev.
2486C-03/02
All page numbers refers to this document.
1
Updated TWI Chapter.
More details regarding use of the TWI Power-down operation and using the TWI as
Master with low TWBRR values are added into the data sheet.
Added the note at the end of the “Bit Rate Generator Unit” on page 165.
Added the description at the end of “Address Match Unit” on page 166.
2
Updated Description of OSCCAL Calibration Byte.
In the data sheet, it was not explained how to take advantage of the calibration
bytes for 2, 4, and 8 MHz Oscillator selections. This is now added in the following
sections:
Improved description of “Oscillator Calibration Register – OSCCAL” on page 29 and
“Calibration Byte” on page 218.
3
Added Some Preliminary Test Limits and Characterization Data.
Removed some of the TBD’s in the following tables and pages:
Table 3 on page 24, Table 15 on page 36, Table 16 on page 40, Table 17 on page
42, Table 99 on page 233, “DC Characteristics TA = -40°C to 85°C, VCC = 2.7V to
5.5V (unless otherwise noted)” on page 234, Table 100 on page 236, and Table 103
on page 238.
4
Updated Programming Figures.
Figure 104 on page 219 and Figure 112 on page 229 are updated to also reflect that
AVCC must be connected during Programming mode.
5
Added a Description on how to Enter Parallel Programming Mode if RESET
Pin is Disabled or if External Oscillators are Selected.
Added a note in section “Enter Programming Mode” on page 221
Changes from Rev.
2486C-03/02 to Rev.
2486D-03/02
All page numbers refers to this document.
1
Updated Typical Start-up Times.
The following tables has been updated:
Table 5, “Start-up Times for the Crystal Oscillator Clock Selection,” on page 26,
Table 6, “Start-up Times for the Low-frequency Crystal Oscillator Clock Selection,”
on page 26, Table 8, “Start-up Times for the External RC Oscillator Clock Selection,” on page 27, and Table 12, “Start-up Times for the External Clock Selection,”
on page 30.
2
16
Added “ATmega8 Typical Characteristics – Preliminary Data” on page 241.
ATmega8(L)
2486HS–AVR–09/02
ATmega8(L)
Changes from Rev.
2486D-03/02 to Rev.
2486E-06/02
All page numbers refers to this document.
1
Updated Some Preliminary Test Limits and Characterization Data
The following tables have been updated:
Table 15, “Reset Characteristics,” on page 36, Table 16, “Internal Voltage Reference Characteristics,” on page 40, DC Characteristics on page 234, Table , “ADC
Characteristics – Preliminary Data,” on page 240.
2
Changes in External Clock Frequency
Added the description at the end of “External Clock” on page 30.
Added period changing data in Table 100, “External Clock Drive,” on page 236.
3
Updated TWI Chapter
More details regarding use of the TWI bit rate prescaler and a Table 65, “TWI Bit
Rate Prescaler,” on page 169.
Changes from Rev.
2486E-06/02 to Rev.
2486F-07/02
All page numbers refers to this document.
1
Changes in “Digital Input Enable and Sleep Modes” on page 53.
2
Addition of OCS2 in “MOSI/OC2 – Port B, Bit 3” on page 57.
3
The following tables has been updated:
Table 51, “CPOL and CPHA Functionality,” on page 129, Table 59, “UCPOL Bit Settings,” on page 154, Table 72, “Analog Comparator Multiplexed Input (1) ,” on
page 190, Table 73, “ADC Conversion Time,” on page 195, Table 75, “Input Channel Selections,” on page 201, and Table 84, “Explanation of Different Variables
used in Figure 103 and the Mapping to the Z-pointer,” on page 215.
5
Changes in “Reading the Calibration Byte” on page 227.
6
Corrected Errors in Cross References.
Changes from Rev.
2486F-07/02 to Rev.
2486G-09/02
All page numbers refers to this document.
Changes from Rev.
2486G-09/02 to Rev.
2486H-09/02
1. Changed the Endurance on the Flash to 10,000 Write/Erase Cycles.
1
Updated Table 104, “ADC Characteristics,” on page 240.
17
2486HS–AVR–09/02
Erratas
The revision letter in this section refers to the revision of the ATmega8 device.
ATmega8 Rev. D
There are no errata for this revision of ATmega8.
ATmega8 Rev. E
There are no errata for this revision of ATmega8.
18
ATmega8(L)
2486HS–AVR–09/02
Atmel Headquarters
Atmel Operations
Corporate Headquarters
Memory
2325 Orchard Parkway
San Jose, CA 95131
TEL 1(408) 441-0311
FAX 1(408) 487-2600
Europe
Atmel Sarl
Route des Arsenaux 41
Case Postale 80
CH-1705 Fribourg
Switzerland
TEL (41) 26-426-5555
FAX (41) 26-426-5500
Asia
Room 1219
Chinachem Golden Plaza
77 Mody Road Tsimhatsui
East Kowloon
Hong Kong
TEL (852) 2721-9778
FAX (852) 2722-1369
Japan
9F, Tonetsu Shinkawa Bldg.
1-24-8 Shinkawa
Chuo-ku, Tokyo 104-0033
Japan
TEL (81) 3-3523-3551
FAX (81) 3-3523-7581
2325 Orchard Parkway
San Jose, CA 95131
TEL 1(408) 441-0311
FAX 1(408) 436-4314
RF/Automotive
Theresienstrasse 2
Postfach 3535
74025 Heilbronn, Germany
TEL (49) 71-31-67-0
FAX (49) 71-31-67-2340
Microcontrollers
2325 Orchard Parkway
San Jose, CA 95131
TEL 1(408) 441-0311
FAX 1(408) 436-4314
La Chantrerie
BP 70602
44306 Nantes Cedex 3, France
TEL (33) 2-40-18-18-18
FAX (33) 2-40-18-19-60
ASIC/ASSP/Smart Cards
1150 East Cheyenne Mtn. Blvd.
Colorado Springs, CO 80906
TEL 1(719) 576-3300
FAX 1(719) 540-1759
Biometrics/Imaging/Hi-Rel MPU/
High Speed Converters/RF Datacom
Avenue de Rochepleine
BP 123
38521 Saint-Egreve Cedex, France
TEL (33) 4-76-58-30-00
FAX (33) 4-76-58-34-80
Zone Industrielle
13106 Rousset Cedex, France
TEL (33) 4-42-53-60-00
FAX (33) 4-42-53-60-01
1150 East Cheyenne Mtn. Blvd.
Colorado Springs, CO 80906
TEL 1(719) 576-3300
FAX 1(719) 540-1759
Scottish Enterprise Technology Park
Maxwell Building
East Kilbride G75 0QR, Scotland
TEL (44) 1355-803-000
FAX (44) 1355-242-743
e-mail
[email protected]
Web Site
http://www.atmel.com
© Atmel Corporation 2002.
Atmel Corporation makes no warranty for the use of its products, other than those expressly contained in the Company’s standard warranty
which is detailed in Atmel’s Terms and Conditions located on the Company’s web site. The Company assumes no responsibility for any errors
which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without notice, and does
not make any commitment to update the information contained herein. No licenses to patents or other intellectual property of Atmel are granted
by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products are not authorized for use as critical
components in life support devices or systems.
ATMEL ® and AVR ® are the registered trademarks of Atmel.
Other terms and product names may be the trademarks of others.
Printed on recycled paper.
2486HS–AVR–09/02
0M
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement