ATMEGA8L-8MUR Atmel, ATMEGA8L-8MUR Datasheet - Page 56

• Manufacturer Part Number: ATMEGA8L-8MUR
• Description: MCU AVR 8KB FLASH 8MHZ 32QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8L-8MUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Unconnected pins
Alternate Port
Functions
56
ATmega8(L)
If some pins are unused, it is recommended to ensure that these pins have a defined level. Even
though most of the digital inputs are disabled in the deep sleep modes as described above, float-
ing inputs should be avoided to reduce current consumption in all other modes where the digital
inputs are enabled (Reset, Active mode and Idle mode).
The simplest method to ensure a defined level of an unused pin, is to enable the internal pull-up.
In this case, the pull-up will be disabled during reset. If low power consumption during reset is
important, it is recommended to use an external pull-up or pull-down. Connecting unused pins
directly to V
accidentally configured as an output.
Most port pins have alternate functions in addition to being general digital I/Os.
how the port pin control signals from the simplified
alternate functions. The overriding signals may not be present in all port pins, but the figure
serves as a generic description applicable to all port pins in the AVR microcontroller family.
Figure 25. Alternate Port Functions
Note:
1. WPx, WDx, RRx, RPx, and RDx are common to all pins within the same port. clk
PUOExn:
PUOVxn:
DDOExn:
DDOVxn:
PVOExn:
PVOVxn:
DIEOExn: Pxn DIGITAL INPUT-ENABLE OVERRIDE ENABLE
DIEOVxn: Pxn DIGITAL INPUT-ENABLE OVERRIDE VALUE
SLEEP:
Pxn
and PUD are common to all ports. All other signals are unique for each pin
CC
or GND is not recommended, since this may cause excessive currents if the pin is
Pxn PULL-UP OVERRIDE ENABLE
Pxn PULL-UP OVERRIDE VALUE
Pxn DATA DIRECTION OVERRIDE ENABLE
Pxn DATA DIRECTION OVERRIDE VALUE
Pxn PORT VALUE OVERRIDE ENABLE
Pxn PORT VALUE OVERRIDE VALUE
SLEEP CONTROL
1
0
1
0
1
0
1
0
(1)
PUOExn
PUOVxn
DDOExn
DDOVxn
PVOExn
PVOVxn
DIEOExn
DIEOVxn
SLEEP
Figure 22 on page 52
PUD:
WDx:
RDx:
RRx:
WPx:
RPx:
clk
DIxn:
AIOxn:
SYNCHRONIZER
D
L
I/O
SET
CLR
:
Q
Q
PULLUP DISABLE
WRITE DDRx
READ DDRx
READ PORTx REGISTER
WRITE PORTx
READ PORTx PIN
I/O CLOCK
DIGITAL INPUT PIN n ON PORTx
ANALOG INPUT/OUTPUT PIN n ON PORTx
D
PINxn
CLR
Q
Q
RESET
RESET
PORTxn
Q
Q
Q
Q
DDxn
CLR
CLR
D
D
can be overridden by
clk
PUD
WDx
RDx
WPx
RRx
DIxn
AIOxn
RPx
I/O
Figure 25
2486Z–AVR–02/11
I/O
, SLEEP,
shows