ATmega128A Atmel Corporation, ATmega128A Datasheet - Page 282

• Manufacturer Part Number: ATmega128A
• Manufacturer: Atmel Corporation

Specifications of ATmega128A

• Flash (kbytes): 128 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): 4096
• 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

25.7
8151H–AVR–02/11
Addressing the Flash During Self-Programming
Note:
The Z-pointer together with RAMPZ are used to address the SPM commands. For details on
how to use the RAMPZ, see “RAMPZ - RAM Page Z Select Register” on page 14.
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/RAMPZ can be used for other operations.
The only SPM operation that does not use the Z-pointer/RAMPZ is setting the Boot Loader Lock
bits. The content of the Z-pointer/RAMPZ is ignored and will have no effect on the operation.
The (E)LPM instruction does also use the Z-pointer/RAMPZ 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 25-3. Addressing the Flash During SPM
Notes:
Bit
ZH (R31)
ZL (R30)
1. “1” means unprogrammed, “0´means programmed
1. The different variables used in
2. PCPAGE and PCWORD are listed in
RAMPZ
PROGRAM
COUNTER
PROGRAM MEMORY
PAGE
Figure
Z15
15
Z7
7
PCMSB
PAGE ADDRESS
WITHIN THE FLASH
BIT
15
25-3. Note that the page erase and page write operations are addressed
ZPCMSB
Z14
14
Z6
6
PCPAGE
Z13
13
Z5
5
Figure 25-3
Table 26-10 on page
Z12
12
Z4
Table 26-11 on page
4
PAGEMSB
ZPAGEMSB
WORD ADDRESS
WITHIN A PAGE
(1)
PCWORD
are listed in
Z11
11
Z3
3
INSTRUCTION WORD
1
PAGE
0
0
Table 25-8 on page
Z10
10
Z2
2
Z - REGISTER
296.
296), the program counter can
ATmega128A
Z9
Z1
9
1
PCWORD[PAGEMSB:0]:
00
01
02
PAGEEND
288.
Z8
Z0
8
0
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