Reading the flash, Programming the eeprom, Reading the eeprom – Rainbow Electronics ATmega128L User Manual

Page 308: Atmega128(l)

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308

ATmega128(L)

2467B–09/01

7.

Write the page using programming instruction 2g.

8.

Poll for Flash write complete using programming instruction 2h, or wait for t

WLRH

(refer to

Table Note: on page 291).

9.

Repeat steps 3 to 8 until all data have been programmed.

Reading the Flash

1.

Enter JTAG instruction PROG_COMMANDS.

2.

Enable Flash read using programming instruction 3a.

3.

Load address using programming instructions 3b and 3c.

4.

Read data using programming instruction 3d.

5.

Repeat steps 3 and 4 until all data have been read.

A more efficient data transfer can be achieved using the PROG_PAGEREAD
instruction:

1.

Enter JTAG instruction PROG_COMMANDS.

2.

Enable Flash read using programming instruction 3a.

3.

Load the page address using programming instructions 3b and 3c. PCWORD
(refer to

Table 124 on page 283) is used to address within one page and must be

written as 0.

4.

Enter JTAG instruction PROG_PAGEREAD.

5.

Read the entire page by shifting out all instruction words in the page, starting
with the LSB of the first instruction in the page and ending with the MSB of the
last instruction in the page. Remember that the first 8 bits shifted out should be
ignored.

6.

Enter JTAG instruction PROG_COMMANDS.

7.

Repeat steps 3 to 6 until all data have been read.

Programming the EEPROM

1.

Enter JTAG instruction PROG_COMMANDS.

2.

Enable EEPROM write using programming instruction 4a.

3.

Load address high byte using programming instruction 4b.

4.

Load address low byte using programming instruction 4c.

5.

Load data using programming instructions 4d and 4e.

6.

Repeat steps 4 and 5 for all data bytes in the page.

7.

Write the data using programming instruction 4f.

8.

Poll for EEPROM write complete using programming instruction 4g, or wait for
t

WLRH

(refer to

Table Note: on page 291).

9.

Repeat steps 3 to 8 until all data have been programmed.

Note that the PROG_PAGELOAD instruction can not be used when programming the
EEPROM

Reading the EEPROM

1.

Enter JTAG instruction PROG_COMMANDS.

2.

Enable EEPROM read using programming instruction 5a.

3.

Load address using programming instructions 5b and 5c.

4.

Read data using programming instruction 5d.

5.

Repeat steps 3 and 4 until all data have been read.

Note that the PROG_PAGEREAD instruction can not be used when reading the
EEPROM

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