ATTINY85-15ST1 Atmel, ATTINY85-15ST1 Datasheet - Page 131

• Manufacturer Part Number: ATTINY85-15ST1
• Description: MCU AVR 8K FLASH 15MHZ 8-SOIC
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY85-15ST1

• Package / Case: 8-SOIC (3.9mm Width)
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 105°C
• Speed: 16MHz
• Number Of I /o: 6
• Eeprom Size: 512 x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 512 x 8
• Program Memory Size: 8KB (8K x 8)
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: USI
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

20.3
20.4
7598H–AVR–07/09
Performing a Page Write
Addressing the Flash During Self-Programming
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 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 20-1. Addressing the Flash During SPM
Note:
Bit
ZH (R31)
ZL (R30)
• The CPU is halted during the Page Write operation.
Z - REGISTER
1. The different variables used in
PROGRAM MEMORY
BIT
PAGE
PROGRAM
COUNTER
15
Z15
Z7
15
7
Figure
PAGE ADDRESS
WITHIN THE FLASH
ZPCMSB
PCMSB
Z14
14
Z6
20-1. Note that the Page Erase and Page Write operations are
6
PCPAGE
Z13
Z5
13
5
Figure 20-1
ZPAGEMSB
PAGEMSB
Table 21-6 on page
PCWORD
Z12
12
Z4
4
WORD ADDRESS
WITHIN A PAGE
(1)
are listed in
1
Z11
0
0
Z3
11
3
INSTRUCTION WORD
PAGE
Table 21-6 on page
Z10
10
Z2
2
137), the Program Counter can
ATtiny25/45/85
Z1
Z9
9
1
PCWORD[PAGEMSB:0]:
00
01
02
PAGEEND
137.
Z8
Z0
8
0
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