
535
42073A-MCU Wireless-02/13
ATmega2564/1284/644RFR2
5. Repeat steps 3 and 4 with address 0x01 and address 0x02 to read the second and
third signature bytes, respectively.
31.10.24 Reading the Calibration Byte
1. Enter JTAG instruction PROG_COMMANDS.
2. Enable Calibration byte read using programming instruction 10a.
3. Load address 0x00 using programming instruction 10b.
4. Read the calibration byte using programming instruction 10c.
31.10.25 Performing Chip Erase of only the EEPROM
The EEPROM must be erased before being programmed. A Chip Erase always erases
command allows erasing only the EEPROM contents. The Flash, Lock and Fuse bits
are not changed.
1. Enter JTAG instruction PROG_COMMANDS.
2. Start EEPROM Chip Erase using programming instruction 1c.
3. Poll for Chip Erase complete using programming instruction 1b, or wait for tWLRH
Note:
13.
The EEPROM memory is also preserved during this special Chip Erase if the
EESAVE Fuse is programmed.
31.10.26 Erasing an EEPROM Page
The EEPROM must be erased before being programmed. A Chip Erase always erases
the entire EEPROM memory. This command allows erasing selected bytes up to an
entire page of EEPROM memory.
1. Enter JTAG instruction PROG_COMMANDS.
2. Enable EEPROM erase using programming instruction 4h.
3. Load High byte of address using programming instruction 4b.
4. Load Low byte of address using programming instruction 4c.
5. Latch the address using programming instructions 4e.
6. Repeat steps 4 and 5 for all data bytes in the page.
7. Erase the data using programming instruction 4f.
8. Poll for EEPROM write complete using programming instruction 4g, or wait for tWLRH
9. Repeat steps 3 to 8 until all data have been erased.
Note that the PROG_PAGELOAD instruction can not be used when programming the
EEPROM.
Note:
1. The EEPROM memory is not preserved during the EEPROM page erase if the
EESAVE Fuse is programmed.