ATMEGA64 datasheet(5/414 Pages) ATMEL

5 / 414 page

2490R–AVR–02/2013

ATmega64(L)

ATmega103

Compatibility Mode

By programming the M103C Fuse, the ATmega64 will be compatible with the ATmega103

regards to RAM, I/O pins and Interrupt Vectors as described above. However, some new fea-

tures in ATmega64 are not available in this compatibility mode, these features are listed below:

•

One USART instead of two, asynchronous mode only. Only the eight least significant bits of

the Baud Rate Register is available.

•

One 16 bits Timer/Counter with two compare registers instead of two 16 bits Timer/Counters

with three compare registers.

•

Two-wire serial interface is not supported.

•

Port G serves alternate functions only (not a general I/O port).

•

Port F serves as digital input only in addition to analog input to the ADC.

•

Boot Loader capabilities is not supported.

•

It is not possible to adjust the frequency of the internal calibrated RC Oscillator.

•

The External Memory Interface can not release any Address pins for general I/O, neither

configure different wait states to different External Memory Address sections.

•

Only EXTRF and PORF exist in the MCUCSR Register.

•

No timed sequence is required for Watchdog Timeout change.

•

Only low-level external interrupts can be used on four of the eight External Interrupt sources.

•

Port C is output only.

•

USART has no FIFO buffer, so Data OverRun comes earlier.

•

The user must have set unused I/O bits to 0 in ATmega103 programs.

Pin Descriptions

VCC

Digital supply voltage.

GND

Ground.

Port A (PA7..PA0)

Port A is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The

Port A output buffers have symmetrical drive characteristics with both high sink and source

capability. As inputs, Port A pins that are externally pulled low will source current if the pull-up

resistors are activated. The Port A pins are tri-stated when a reset condition becomes active,

even if the clock is not running.

Port A also serves the functions of various special features of the ATmega64 as listed on page

73.

Port B (PB7..PB0)

Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The

Port B output buffers have symmetrical drive characteristics with both high sink and source

capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up

resistors are activated. The Port B pins are tri-stated when a reset condition becomes active,

even if the clock is not running.

Port B also serves the functions of various special features of the ATmega64 as listed on page

74.

ATMEGA64 Datasheet(PDF) 5 Page - ATMEL Corporation

ATMEGA64 Datasheet(HTML) 5 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