ATMEGA324P-A15MZ Atmel, ATMEGA324P-A15MZ Datasheet - Page 250

• Manufacturer Part Number: ATMEGA324P-A15MZ
• Description: MCU AVR 32KB FLASH 15MHZ 44-VQFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA324P-A15MZ

• Package / Case: 44-VQFN Exposed Pad
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 32
• Eeprom Size: 1K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Program Memory Size: 32KB (32K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Self-Programming
the Flash
250
ATmega32(L)
Figure 126. Addressing the Flash during SPM
Notes:
The program memory is updated in a page by page fashion. Before programming a page with
the data stored in the temporary page buffer, the page must be erased. The temporary page buf-
fer is filled one word at a time using SPM and the buffer can be filled either before the page
erase command or between a page erase and a page write operation:
Alternative 1, fill the buffer before a Page Erase
•
•
•
Alternative 2, fill the buffer after Page Erase
•
•
•
If only a part of the page needs to be changed, the rest of the page must be stored (for example
in the temporary page buffer) before the erase, and then be rewritten. When using alternative 1,
the Boot Loader provides an effective Read-Modify-Write feature which allows the user software
to first read the page, do the necessary changes, and then write back the modified data. If alter-
native 2 is used, it is not possible to read the old data while loading since the page is already
erased. The temporary page buffer can be accessed in a random sequence. It is essential that
the page address used in both the page erase and page write operation is addressing the same
page. See
code example.
Fill temporary page buffer
Perform a Page Erase
Perform a Page Write
Perform a Page Erase
Fill temporary page buffer
Perform a Page Write
Z - REGISTER
1. The different variables used in
2. PCPAGE and PCWORD are listed in
PROGRAM MEMORY
BIT
“Simple Assembly Code Example for a Boot Loader” on page 253
PROGRAM
COUNTER
15
PAGE
PAGE ADDRESS
WITHIN THE FLASH
ZPCMSB
PCMSB
PCPAGE
Figure 126
ZPAGEMSB
PAGEMSB
PCWORD
“Page Size” on page
(1)
WORD ADDRESS
WITHIN A PAGE
are listed in
1
0
0
INSTRUCTION WORD
PAGE
Table 101 on page
258.
PCWORD[PAGEMSB:0]:
00
01
02
PAGEEND
255.
for an assembly
2503N–AVR–06/08