atmega323l ATMEL Corporation, atmega323l Datasheet - Page 193

• Manufacturer Part Number: atmega323l
• Description: Atmega323 8-bit Avr Microcontroller With 32k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Reading the Flash
Reading the EEPROM
1457G–AVR–09/03
3. Wait until to RDY/BSY goes high before programming the next byte.
The loaded command and address are retained in the device during programming. For
efficient programming, the following should be considered.
•
•
•
These considerations also applies to Flash, EEPROM and Signature bytes reading.
Figure 96. Programming the EEPROM Waveforms
The algorithm for reading the Flash memory is as follows (refer to “Programming the
Flash” on page 190 for details on Command and Address loading):
1. A: Load Command “0000 0010”.
2. H: Load Address High Byte ($00 - $3F)
3. B: Load Address Low Byte ($00 - $FF)
4. Set OE to “0”, and BS1 to “0”. The Flash word Low Byte can now be read at
5. Set BS to “1”. The Flash word High Byte can now be read at DATA.
6. Set OE to “1”.
The algorithm for reading the EEPROM Memory is as follows (refer to “Programming the
Flash” on page 190 for details on Command and Address loading):
1. A: Load Command “0000 0011”.
2. H: Load Address High Byte ($00 - $03)
3. B: Load Address ($00 - $FF)
4. Set OE to “0”, and BS1 to “0”. The EEPROM Data byte can now be read at
RDY/BSY
RESET
PAGEL
XTAL1
DATA
(See Figure 96 for signal waveforms)
The command needs only be loaded once when writing or reading multiple memory
locations.
Address High Byte needs only be loaded before programming a new 256 byte
window in the EEPROM.
Skip writing the data value $FF, that is the contents of the entire EEPROM after a
Chip Erase.
DATA.
DATA.
XA1
XA2
BS1
BS2
WR
OE
+12V
$11
ADDR. HIGH
ADDR. LOW
DA TA LOW
ATmega323(L)
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