ATmega8535 Atmel Corporation, ATmega8535 Datasheet - Page 247

• Manufacturer Part Number: ATmega8535
• Manufacturer: Atmel Corporation

Specifications of ATmega8535

• Flash (kbytes): 8 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 3
• 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): 0.5
• 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: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Programming the Lock Bits
Reading the Fuse and Lock
Bits
Reading the Signature Bytes
Reading the Calibration Byte
2502K–AVR–10/06
The algorithm for programming the Lock bits is as follows (refer to “Programming the
Flash” on page 243 for details on Command and Data loading):
1. A: Load Command “0010 0000”.
2. C: Load Data Low Byte. Bit n = “0” programs the Lock bit.
3. Give WR a negative pulse and wait for RDY/BSY to go high.
The Lock bits can only be cleared by executing Chip Erase.
The algorithm for reading the Fuse and Lock bits is as follows (refer to “Programming
the Flash” on page 243 for details on Command loading):
1. A: Load Command “0000 0100”.
2. Set OE to “0”, BS2 to “0”, and BS1 to “0”. The status of the Fuse Low bits can
3. Set OE to “0”, BS2 to “1”, and BS1 to “1”. The status of the Fuse High bits can
4. Set OE to “0”, BS2 to “0”, and BS1 to “1”. The status of the Lock bits can now be
5. Set OE to “1”.
Figure 120. Mapping Between BS1, BS2 and the Fuse- and Lock Bits During Read
The algorithm for reading the Signature bytes is as follows (refer to “Programming the
Flash” on page 243 for details on Command and Address loading):
1. A: Load Command “0000 1000”.
2. B: Load Address Low Byte (0x00 - 0x02).
3. Set OE to “0”, and BS to “0”. The selected Signature byte can now be read at
4. Set OE to “1”.
The algorithm for reading the Calibration byte is as follows (refer to “Programming the
Flash” on page 243 for details on Command and Address loading):
1. A: Load Command “0000 1000”.
2. B: Load Address Low Byte, 0x00.
3. Set OE to “0”, and BS1 to “1”. The Calibration byte can now be read at DATA.
4. Set OE to “1”.
now be read at DATA (“0” means programmed).
now be read at DATA (“0” means programmed).
read at DATA (“0” means programmed).
DATA.
Fuse Low Byte
Lock Bits
Fuse High Byte
BS2
0
1
BS1
ATmega8535(L)
0
1
DATA
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