ATmega165 datasheet(278/336 Pages) ATMEL

278 / 336 page

278

ATmega165/V

2573G–AVR–07/09

Programming the Lock Bits

Enter JTAG instruction PROG_COMMANDS.

Enable Lock bit write using programming instruction 7a.

Load data using programming instructions 7b. A bit value of “0” will program the

corresponding lock bit, a “1” will leave the lock bit unchanged.

Write Lock bits using programming instruction 7c.

Poll for Lock bit write complete using programming instruction 7d, or wait for

WLRH (refer to Table 112 on page 259).

Reading the Fuses and Lock

Bits

Enter JTAG instruction PROG_COMMANDS.

Enable Fuse/Lock bit read using programming instruction 8a.

To read all Fuses and Lock bits, use programming instruction 8e.

To only read Fuse High byte, use programming instruction 8b.

To only read Fuse Low byte, use programming instruction 8c.

To only read Lock bits, use programming instruction 8d.

Reading the Signature Bytes

Enter JTAG instruction PROG_COMMANDS.

Enable Signature byte read using programming instruction 9a.

Load address 0x00 using programming instruction 9b.

Read first signature byte using programming instruction 9c.

Repeat steps 3 and 4 with address 0x01 and address 0x02 to read the second

and third signature bytes, respectively.

Reading the Calibration Byte

Enter JTAG instruction PROG_COMMANDS.

Enable Calibration byte read using programming instruction 10a.

Load address 0x00 using programming instruction 10b.

Read the calibration byte using programming instruction 10c.

ATmega165 Datasheet(PDF) 278 Page - ATMEL Corporation