ATMEGA32A-MNR Atmel, ATMEGA32A-MNR Datasheet - Page 258

• Manufacturer Part Number: ATMEGA32A-MNR
• Description: IC MCU AVR 32K 16MHZ 44VQFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32A-MNR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

25.7
8155C–AVR–02/11
Addressing the Flash during Self-Programming
Table 25-4.
Note:
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
addressed 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 program-
ming 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 25-3. Addressing the Flash during SPM
Bit
ZH (R31)
ZL (R30)
BOOTRST
Z - REGISTER
1
0
1. “1” means unprogrammed, “0” means programmed
PROGRAM MEMORY
BIT
PROGRAM
COUNTER
Boot Reset Fuse
15
PAGE
Z15
Z7
15
7
Reset Address
Reset Vector = Application reset (address $0000)
Reset Vector = Boot Loader reset (see
Figure
PAGE ADDRESS
WITHIN THE FLASH
ZPCMSB
PCMSB
Z14
Z6
14
25-3. Note that the Page Erase and Page Write operations are
6
PCPAGE
(1)
Z13
13
Z5
5
ZPAGEMSB
PAGEMSB
PCWORD
Table 26-5 on page
Z12
12
Z4
4
WORD ADDRESS
WITHIN A PAGE
(1)
1
0
0
Table 25-6 on page
Z11
11
Z3
3
INSTRUCTION WORD
PAGE
Z10
Z2
10
2
269), the Program Counter can
263)
Z9
Z1
ATmega32A
9
1
PCWORD[PAGEMSB:0]:
00
01
02
PAGEEND
Z8
Z0
8
0
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