ATMEGA8HVD-4MX Atmel, ATMEGA8HVD-4MX Datasheet - Page 122

• Manufacturer Part Number: ATMEGA8HVD-4MX
• Description: MCU AVR 8K FLASH 2.1-8V 4MHZ QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8HVD-4MX

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 2.4 V
• Data Converters: A/D 1x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 18-MLF® Exposed Pad (Staggered Leads), DFN
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Connectivity: -

23.4
23.5
122
Performing a Page Write
Addressing the Flash During Self-Programming
ATmega4HVD/8HVD
To execute Page Write, set up the address in the Z-pointer, write “00000101” to SPMCSR and
execute SPM within four clock cycles after writing SPMCSR. The data in R1 and R0 is
ignored. The page address must be written to PCPAGE. Other bits in the Z-pointer must be
written to zero during this operation.
• The CPU is halted during the Page Write operation.
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 software addresses the
same page in both the Page Erase and Page Write operation.
The LPM instruction uses 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 23-1. Addressing the Flash During SPM
Note:
Bit
ZH (R31)
ZL (R30)
Z - REGISTER
1. The different variables used in
PROGRAM MEMORY
BIT
PAGE
PROGRAM
COUNTER
15
Z15
15
Z7
7
PAGE ADDRESS
WITHIN THE FLASH
ZPCMSB
PCMSB
Figure
Z14
Z6
14
6
PCPAGE
23-1. Note that the Page Erase and Page Write operations are
Z13
Z5
13
5
Figure 23-1
ZPAGEMSB
PAGEMSB
Table 24-6 on page
PCWORD
Z12
12
Z4
4
WORD ADDRESS
WITHIN A PAGE
(1)
1
are listed in
Z11
0
0
11
Z3
3
INSTRUCTION WORD
PAGE
Z10
Z2
10
2
Table 24-6 on page
131), the Program Counter can
Z9
Z1
9
1
PCWORD[PAGEMSB:0]:
00
01
02
PAGEEND
Z8
Z0
8052B–AVR–09/08
8
0
131.