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Programming the eeprom, Atmega8515(l), Figure 76. programming the flash waveforms – Rainbow Electronics ATmega8515L User Manual

Page 183

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183

ATmega8515(L)

2512A–AVR–04/02

Figure 76. Programming the Flash Waveforms

Note:

“XX” is don’t care. The letters refer to the programming description above.

Programming the EEPROM

The EEPROM is organized in pages, see Table 90 on page 179. 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 181 for details on
Command, Address and Data loading):

1.

A: Load Command “0001 0001”.

2.

G: Load Address High Byte ($00 - $FF).

3.

B: Load Address Low Byte ($00 - $FF).

4.

C: Load Data ($00 - $FF).

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 77 for signal waveforms.)

RDY/BSY

WR

OE

RESET +12V

PAGEL

BS2

$10

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