Datasheet

174
7701F–AVR–10/12
Atmel ATtiny24/44/84 [Preliminary]
Figure 21-5. High-voltage Serial Programming Waveforms
21.8.5 Programming the EEPROM
The EEPROM is organized in pages, see Table 22-8 on page 185. When programming the
EEPROM, the data are latched into a page buffer. This allows one page of data to be pro-
grammed simultaneously. The programming algorithm for the EEPROM data memory is as
follows (refer to Table 21-15 on page 175):
1. Load "Write EEPROM" command.
2. Load EEPROM page buffer.
3. Program EEPROM page. Wait after Instr. 2 until SDO goes high for the page pro-
gramming cycle to finish.
4. Repeat 2 and 3 until the entire EEPROM is programmed, or until all data has been
programmed.
5. End page programming by loading "No Operation" command.
21.8.6 Reading the Flash
The algorithm for reading the Flash memory is as follows (refer to Table 21-15 on page 175):
1. Load "Read Flash" command.
2. Read Flash Low and High Bytes. The contents at the selected address are available
at serial output SDO.
21.8.7 Reading the EEPROM
The algorithm for reading the EEPROM memory is as follows (refer to Table 21-15 on page
175):
1. Load "Read EEPROM" command.
2. Read EEPROM byte. The contents at the selected address are available at serial out-
put SDO.
21.8.8 Programming and Reading the Fuse and Lock Bits
The algorithms for programming and reading the Fuse Low/High bits and Lock bits are shown
in Table 21-15 on page 175.
21.8.9 Reading the Signature Bytes and Calibration Byte
The algorithms for reading the Signature bytes and Calibration byte are shown in Table 21-15
on page 175.
21.8.10 Power-off sequence
Set SCI to “0”. Set RESET to “1”. Turn V
CC
power off.
MSB
MSB
MSB LSB
LSB
LSB
012345678910
SDI
PB0
SII
PB1
SDO
PB2
SCI
PB3