ATmega64 Atmel Corporation, ATmega64 Datasheet - Page 283

• Manufacturer Part Number: ATmega64
• Manufacturer: Atmel Corporation

Specifications of ATmega64

• Flash (kbytes): 64 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 53
• Ext Interrupts: 8
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• 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): 4
• Eeprom (bytes): 2048
• 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: 4
• Output Compare Channels: 8
• Input Capture Channels: 2
• Pwm Channels: 7
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Addressing the
Flash During Self-
programming
2490Q–AVR–06/10
The Z-pointer is used to address the SPM commands.
Since the Flash is organized in pages (see
be treated as having two different sections. One section, consisting of the least significant bits, is
addressing the words within a page, while the most significant bits are addressing the pages.
This is shown in
independently. Therefore, it is of major importance that the Boot Loader software addresses the
same page in both the Page Erase and Page Write operation. Once a programming operation is
initiated, the address is latched and the Z-pointer can be used for other operations.
The only SPM operation that does not use the Z-pointer is Setting the Boot Loader Lock bits.
The content of the Z-pointer is ignored and will have no effect on the operation. The LPM
instruction does also use the Z-pointer to store the address. Since this instruction addresses the
Flash byte-by-byte, also the LSB (Bit Z0) of the Z-pointer is used.
Figure 137. Addressing the Flash during SPM
Notes:
Bit
ZH (R31)
ZL (R30)
Z - REGISTER
1. The different variables used in
2. PCPAGE and PCWORD are listed in
PROGRAM MEMORY
BIT
Z15
PROGRAM
COUNTER
15
Z7
15
PAGE
7
Figure
PAGE ADDRESS
WITHIN THE FLASH
ZPCMSB
137. Note that the Page Erase and Page Write operations are addressed
PCMSB
Z14
Z6
14
6
PCPAGE
Z13
13
Z5
5
Figure 137
Z12
12
Z4
4
ZPAGEMSB
PAGEMSB
PCWORD
Table 123 on page
Table 124 on page
(1)
WORD ADDRESS
WITHIN A PAGE
Z11
Table 2 on page 283
11
Z3
are listed in
3
1
0
0
INSTRUCTION WORD
Z10
10
Z2
2
Table 113 on page
PAGE
296.
296), the Program Counter can
Z9
Z1
9
1
ATmega64(L)
Z8
Z0
8
0
PCWORD[PAGEMSB:0]:
00
01
02
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