Data Sheet

305
8161D–AVR–10/09
ATmega48PA/88PA/168PA/328P
5. E: Latch data (give PAGEL a positive pulse).
K: Repeat 3 through 5 until the entire buffer is filled.
L: Program EEPROM page
1. Set BS1 to “0”.
2. Give WR
a negative pulse. This starts programming of the EEPROM page. RDY/BSY
goes low.
3. Wait until to RDY/BSY
goes high before programming the next page (See Figure 27-4 for
signal waveforms).
Figure 27-4. Programming the EEPROM Waveforms
27.7.6 Reading the Flash
The algorithm for reading the Flash memory is as follows (refer to ”Programming the Flash” on
page 302 for details on Command and Address loading):
1. A: Load Command “0000 0010”.
2. G: Load Address High Byte (0x00 - 0xFF).
3. B: Load Address Low Byte (0x00 - 0xFF).
4. Set OE
to “0”, and BS1 to “0”. The Flash word low byte can now be read at DATA.
5. Set BS1 to “1”. The Flash word high byte can now be read at DATA.
6. Set OE
to “1”.
27.7.7 Reading the EEPROM
The algorithm for reading the EEPROM memory is as follows (refer to ”Programming the Flash”
on page 302 for details on Command and Address loading):
1. A: Load Command “0000 0011”.
2. G: Load Address High Byte (0x00 - 0xFF).
3. B: Load Address Low Byte (0x00 - 0xFF).
4. Set OE
to “0”, and BS1 to “0”. The EEPROM Data byte can now be read at DATA.
5. Set OE
to “1”.
RDY/BSY
WR
OE
RESET +12V
PAGEL
BS2
0x11 ADDR. HIGH
DATA
ADDR. LOW DATA ADDR. LOW DATA XX
XA1
XA0
BS1
XTAL1
XX
AGBCEB C EL
K