attiny24v ATMEL Corporation, attiny24v Datasheet - Page 169

• Manufacturer Part Number: attiny24v
• Description: 8-bit Avr Microcontroller With 2/4/8k Bytes Insystem Programmable Flash
• Manufacturer: ATMEL Corporation

19.7.2
19.7.3
19.7.4
8006H–AVR–10/09
Considerations for Efficient Programming
Chip Erase
Programming the Flash
The loaded command and address are retained in the device during programming. For efficient
programming, the following should be considered.
The Chip Erase will erase the Flash and EEPROM
not reset until the Program memory has been completely erased. The Fuse bits are not
changed. A Chip Erase must be performed before the Flash and/or EEPROM are re-
programmed.
Note:
The Flash is organized in pages, see
the program data is latched into a page buffer. This allows one page of program data to be pro-
grammed simultaneously. The following procedure describes how to program the entire Flash
memory:
When writing or reading serial data to the ATtiny24/44/84, data is clocked on the rising edge of
the serial clock, see
page 184
• The command needs only be loaded once when writing or reading multiple memory
• Skip writing the data value 0xFF that is the contents of the entire EEPROM (unless the
• Address High byte needs only be loaded before programming or reading a new 256 word
1. Load command “Chip Erase” (see
2. Wait after Instr. 3 until SDO goes high for the “Chip Erase” cycle to finish.
3. Load Command “No Operation”.
1. Load Command “Write Flash” (see
2. Load Flash Page Buffer.
3. Load Flash High Address and Program Page. Wait after Instr. 3 until SDO goes high for
4. Repeat 2 through 3 until the entire Flash is programmed or until all data has been
5. End Page Programming by Loading Command “No Operation”.
locations.
EESAVE Fuse is programmed) and Flash after a Chip Erase.
window in Flash or 256 byte EEPROM. This consideration also applies to Signature bytes
reading.
the “Page Programming” cycle to finish.
programmed.
1. The EEPROM memory is preserved during Chip Erase if the EESAVE Fuse is programmed.
for details.
Figure 20-6 on page
“Page Size” on page
Table 19-16 on page
Table 19-16 on page
184,
Figure 19-3 on page 167
(1)
memories plus Lock bits. The Lock bits are
162. When programming the Flash,
171).
171).
ATtiny24/44/84
and
Table 20-13 on
169