ATmega8 Atmel Corporation, ATmega8 Datasheet - Page 220

• Manufacturer Part Number: ATmega8
• Manufacturer: Atmel Corporation

Specifications of ATmega8

• Flash (kbytes): 8 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 2
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 1
• Pwm Channels: 3
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

220
ATmega8(L)
Table 91. Pin Name Mapping (Continued)
Table 92. Pin Values used to Enter Programming Mode
Table 93. XA1 and XA0 Coding
Table 94. Command Byte Bit Coding
Signal Name in
Programming Mode
PAGEL
BS2
DATA
XA1
0
0
1
1
Command Byte
1000 0000
0100 0000
0010 0000
0001 0000
0001 0001
0000 1000
0000 0100
0000 0010
0000 0011
PAGEL
XA0
XA1
XA0
BS1
Pin
0
1
0
1
Action when XTAL1 is Pulsed
Load Flash or EEPROM Address (High or low address byte determined by BS1)
Load Data (High or Low data byte for Flash determined by BS1)
Load Command
No Action, Idle
Command Executed
Chip Erase
Write Fuse Bits
Write Lock Bits
Write Flash
Write EEPROM
Read Signature Bytes and Calibration byte
Read Fuse and Lock Bits
Read Flash
Read EEPROM
{PC[1:0]: PB[5:0]}
Pin Name
PD7
PC2
Prog_enable[3]
Prog_enable[2]
Prog_enable[1]
Prog_enable[0]
Symbol
I/O
I/O
I
I
Function
Program memory and EEPROM Data
Page Load
Byte Select 2 (“0” selects Low byte, “1”
selects 2’nd High byte)
Bi-directional Data bus (Output when OE is
low)
Value
0
0
0
0
2486Z–AVR–02/11