5 programming the eeprom, Figure 24-3, Figure 24-3. programming the flash waveforms – Rainbow Electronics ATmega64C1 User Manual
Page 299
299
7647A–AVR–02/08
ATmega32/64/M1/C1
Figure 24-3. Programming the Flash Waveforms
Note:
1. “XX” is don’t care. The letters refer to the programming description above.
24.8.5
Programming the EEPROM
The EEPROM is organized in pages, see
. 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
“Programming the Flash” on page 297
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
for
signal waveforms).
RDY/BSY
WR
OE
RESET +12V
PAGEL
BS2
0x10
ADDR. LOW
ADDR. HIGH
DATA
DATA LOW
DATA HIGH
ADDR. LOW
DATA LOW
DATA HIGH
XA1
XA0
BS1
XTAL1
XX
XX
XX
A
B
C
D
E
B
C
D
E
G
H
F