Figure 25-3. Programming the Flash Waveforms(1)
F
A
B
C
D
E
B
C
D
E
G
H
0x10
ADDR. LOW DATA LOW DATA HIGH
XX
ADDR. LOW DATA LOW DATA HIGH
XX
ADDR. HIGH
XX
DATA
XA1
XA0
BS1
XTAL1
WR
RDY/BSY
RESET +12V
OE
PAGEL
BS2
Note:
1. “XX” is don’t care. The letters refer to the programming description above.
25.8.5 Programming the EEPROM
The EEPROM is organized in pages, see Table 25-13 on page 260. 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 25.8.4 “Programming the Flash” on page 262 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 on page 265 for signal
waveforms).
264
ATmega16/32/64/M1/C1 [DATASHEET]
7647O–AVR–01/15
MICROCHIP [ MICROCHIP ]
