Datasheet

ATmega48/88/168 Automotive [DATASHEET]
7530K–AVR–07/14
250
Figure 25-3. Programming the Flash Waveforms
(1)
Note: 1. “XX” is don’t care. The letters refer to the programming description above.
25.7.5 Programming the EEPROM
The EEPROM is organized in pages, see Table 25-13 on page 247. When programming the EEPROM, the program data is
latched into a page buffer. This allows one page of data to be programmed simultaneously. The programming algorithm for
the EEPROM data memory is as follows (refer to Section 25.7.4 “Programming the Flash” on page 248 for details on
command, address and data loading):
1. A: Load command “0001 0001”.
2. G: Load address high byte (0x00 - 0xFF).
3. B: Load address low byte (0x00 - 0xFF).
4. C: Load data (0x00 - 0xFF).
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 25-4 for signal waveforms).
0x10 ADDR. LOW
AB
DATA
XA1
XA0
BS1
BS2
XTAL1
WR
PAGEL
RDY/BSY
OE
RESET +12V
DATA LOW DATA HIGH
CD
ADDR. LOW
B
DATA LOW DATA HIGH
CD
F
XX
E
XX
E
XXADDR. HIGH
GH