ATMEGA640 datasheet(342/436 Pages) MICROCHIP

342 / 436 page

342

ATmega640/V-1280/V-1281/V-2560/V-2561/V [DATASHEET]

DS40002211A

Figure 30-11. Serial Programming Instruction example

30.8.4

Serial Programming Characteristics

For characteristics of the Serial Programming module, see “SPI Timing Characteristics” on page 363.

Figure 30-12. Serial Programming Waveforms

30.9 Programming via the JTAG Interface

Programming through the JTAG interface requires control of the four JTAG specific pins: TCK, TMS, TDI, and

TDO. Control of the reset and clock pins is not required.

To be able to use the JTAG interface, the JTAGEN Fuse must be programmed. The device is default shipped with

the fuse programmed. In addition, the JTD bit in MCUCR must be cleared. Alternatively, if the JTD bit is set, the

external reset can be forced low. Then, the JTD bit will be cleared after two chip clocks, and the JTAG pins are

available for programming. This provides a means of using the JTAG pins as normal port pins in Running mode

Byte 1

Byte 2

Byte 3

Byte 4

Adr LSB

Bit 15 B

Serial Programming Instruction

Program Memory/

EEPROM Memory

Page 0

Page 1

Page 2

Page N-1

Page Buffer

Write Program Memory Page/

Write EEPROM Memory Page

Load Program Memory Page (High/Low Byte)/

Load EEPROM Memory Page (page access)

Byte 1

Byte 2

Byte 3

Byte 4

Bit 15 B

Adr MSB

Page Offset

Page Number

Adr

dr M

r MS

Adr

dr LS

LSB

MSB

LSB

SERIAL CLOCK INPUT

(SCK)

SERIAL DATA INPUT

(MOSI)

(MISO)

SAMPLE

SERIAL DATA OUTPUT

ATMEGA640 Datasheet(PDF) 342 Page - Microchip Technology

ATMEGA640 Datasheet(HTML) 342 Page - Microchip Technology

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