ATmega16U4 datasheet(378/408 Pages) ATMEL

378 / 408 page

378

7766D–AVR–01/09

ATmega16U4/ATmega32U4

Enter JTAG instruction PROG_COMMANDS.

Enable Flash read using programming instruction 3a.

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

to Table 28-11 on page 353) is used to address within one page and must be written as

Enter JTAG instruction PROG_PAGEREAD.

Read the entire page (or Flash) by shifting out all instruction words in the page (or

Flash), 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.

Enter JTAG instruction PROG_COMMANDS.

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

28.9.18

Programming the EEPROM

Before programming the EEPROM a Chip Erase must be performed, see “Performing Chip

Erase” on page 377.

Enter JTAG instruction PROG_COMMANDS.

Enable EEPROM write using programming instruction 4a.

Load address High byte using programming instruction 4b.

Load address Low byte using programming instruction 4c.

Load data using programming instructions 4d and 4e.

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

Write the data using programming instruction 4f.

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

WLRH

(refer to Table 28-13 on page 362).

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.

28.9.19

Reading the EEPROM

Enter JTAG instruction PROG_COMMANDS.

Enable EEPROM read using programming instruction 5a.

Load address using programming instructions 5b and 5c.

Read data using programming instruction 5d.

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.

28.9.20

Programming the Fuses

Enter JTAG instruction PROG_COMMANDS.

Enable Fuse write using programming instruction 6a.

Load data high byte using programming instructions 6b. A bit value of “0” will program

the corresponding fuse, a “1” will unprogram the fuse.

Write Fuse High byte using programming instruction 6c.

Poll for Fuse write complete using programming instruction 6d, or wait for t

WLRH (refer to

Table 28-13 on page 362).

ATmega16U4 Datasheet(PDF) 378 Page - ATMEL Corporation

ATmega16U4 Datasheet(HTML) 378 Page - ATMEL Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL