ATmega324P datasheet(278/377 Pages) ATMEL

278 / 377 page

278

7674F–AVR–09/09

ATmega164P/324P/644P

23.8

23.8.1

MCUCR – MCU Control Register

The MCU Control Register contains control bits for general MCU functions.

• Bits 7 – JTD: JTAG Interface Disable

When this bit is zero, the JTAG interface is enabled if the JTAGEN Fuse is programmed. If this

bit is one, the JTAG interface is disabled. In order to avoid unintentional disabling or enabling of

the JTAG interface, a timed sequence must be followed when changing this bit: The application

software must write this bit to the desired value twice within four cycles to change its value. Note

that this bit must not be altered when using the On-chip Debug system.

23.8.2

MCUSR – MCU Status Register

The MCU Status Register provides information on which reset source caused an MCU reset.

• Bit 4 – JTRF: JTAG Reset Flag

This bit is set if a reset is being caused by a logic one in the JTAG Reset Register selected by

the JTAG instruction AVR_RESET. This bit is reset by a Power-on Reset, or by writing a logic

zero to the flag.

Bit

0x35 (0x55)

JTD

BODS

BODSE

PUD

–

IVSEL

IVCE

MCUCR

Read/Write

R/W

Initial Value

Bit

765

432

0x34 (0x54)

–

–JTRF

WDRF

BORF

EXTRF

PORF

MCUSR

Read/Write

R/W

Initial Value

See Bit Description

ATmega324P Datasheet(PDF) 278 Page - ATMEL Corporation

ATmega324P Datasheet(HTML) 278 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