atmega3250v-8auatmega325v-8ai ATMEL Corporation, atmega3250v-8auatmega325v-8ai Datasheet - Page 294

• Manufacturer Part Number: atmega3250v-8auatmega325v-8ai
• Description: Atmega3250 8-bit Microcontroller With In-system Programmable Flash
• Manufacturer: ATMEL Corporation

27.8.18
27.8.19
27.8.20
294
ATmega325/3250/645/6450
Programming the EEPROM
Reading the EEPROM
Programming the Fuses
3. Load the page address using programming instructions 3b and 3c. PCWORD (refer to
4. Enter JTAG instruction PROG_PAGEREAD.
5. Read the entire page (or Flash) by shifting out all instruction words in the page (or Flash),
6. Enter JTAG instruction PROG_COMMANDS.
7. Repeat steps 3 to 6 until all data have been read.
Before programming the EEPROM a Chip Erase must be performed, see “Performing Chip
Erase” on page 293.
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
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.
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.
1. Enter JTAG instruction PROG_COMMANDS.
2. Enable Fuse write using programming instruction 6a.
3. Load data high byte using programming instructions 6b. A bit value of “0” will program the
4. Write Fuse High byte using programming instruction 6c.
5. Poll for Fuse write complete using programming instruction 6d, or wait for t
6. Load data low byte using programming instructions 6e. A “0” will program the fuse, a “1”
7. Write Fuse low byte using programming instruction 6f.
Table 27-10 on page
starting with the LSB of the first instruction in the page (Flash) and ending with the MSB
of the last instruction in the page (Flash). The Capture-DR state both captures the data
from the Flash, and also auto-increments the program counter after each word is read.
Note that Capture-DR comes before the shift-DR state. Hence, the first byte which is
shifted out contains valid data.
(refer to
corresponding fuse, a “1” will unprogram the fuse.
Table 27-12 on page
will unprogram the fuse.
Table 27-12 on page
269) is used to address within one page and must be written as 0.
278).
278).
WLRH
2570L–AVR–08/07
(refer to
WLRH