ATMEGA48A-PU Atmel, ATMEGA48A-PU Datasheet - Page 55

IC MCU AVR 4K FLASH 28PDIP

ATMEGA48A-PU

Manufacturer Part Number
ATMEGA48A-PU
Description
IC MCU AVR 4K FLASH 28PDIP
Manufacturer
Atmel
Series
AVR® ATmegar
Datasheets

Specifications of ATMEGA48A-PU

Core Processor
AVR
Core Size
8-Bit
Speed
20MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
23
Program Memory Size
4KB (2K x 16)
Program Memory Type
FLASH
Eeprom Size
256 x 8
Ram Size
512 x 8
Voltage - Supply (vcc/vdd)
1.8 V ~ 5.5 V
Data Converters
A/D 6x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
28-DIP (0.300", 7.62mm)
Controller Family/series
Atmega
No. Of I/o's
23
Eeprom Memory Size
256Byte
Ram Memory Size
512Byte
Cpu Speed
20MHz
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Lead free / RoHS Compliant

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ATMEGA48A-PU
Manufacturer:
Microchip Technology
Quantity:
1 051
10.9
10.9.1
10.9.2
8271C–AVR–08/10
Register Description
MCUSR – MCU Status Register
WDTCSR – Watchdog Timer Control Register
The MCU Status Register provides information on which reset source caused an MCU reset.
• Bit 7:4: Reserved
These bits are unused bits in the ATmega48A/48PA/88A/88PA/168A/168PA/328/328P, and will
always read as zero.
• Bit 3 – WDRF: Watchdog System Reset Flag
This bit is set if a Watchdog System Reset occurs. The bit is reset by a Power-on Reset, or by
writing a logic zero to the flag.
• Bit 2 – BORF: Brown-out Reset Flag
This bit is set if a Brown-out Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 1 – EXTRF: External Reset Flag
This bit is set if an External Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 0 – PORF: Power-on Reset Flag
This bit is set if a Power-on Reset occurs. The bit is reset only by writing a logic zero to the flag.
To make use of the Reset Flags to identify a reset condition, the user should read and then
Reset the MCUSR as early as possible in the program. If the register is cleared before another
reset occurs, the source of the reset can be found by examining the Reset Flags.
• Bit 7 – WDIF: Watchdog Interrupt Flag
This bit is set when a time-out occurs in the Watchdog Timer and the Watchdog Timer is config-
ured for interrupt. WDIF is cleared by hardware when executing the corresponding interrupt
handling vector. Alternatively, WDIF is cleared by writing a logic one to the flag. When the I-bit in
SREG and WDIE are set, the Watchdog Time-out Interrupt is executed.
• Bit 6 – WDIE: Watchdog Interrupt Enable
When this bit is written to one and the I-bit in the Status Register is set, the Watchdog Interrupt is
enabled. If WDE is cleared in combination with this setting, the Watchdog Timer is in Interrupt
Mode, and the corresponding interrupt is executed if time-out in the Watchdog Timer occurs. If
WDE is set, the Watchdog Timer is in Interrupt and System Reset Mode. The first time-out in the
ATmega48A/48PA/88A/88PA/168A/168PA/328/328
Bit
0x34 (0x54)
Read/Write
Initial Value
Bit
(0x60)
Read/Write
Initial Value
WDIF
R/W
7
0
R
7
0
WDIE
R/W
6
0
R
6
0
WDP3
R/W
5
0
R
5
0
WDCE
R/W
4
0
R
4
0
WDE
WDRF
R/W
R/W
3
X
3
WDP2
R/W
BORF
See Bit Description
R/W
2
0
2
WDP1
R/W
EXTRF
R/W
1
0
1
WDP0
R/W
PORF
0
0
R/W
0
WDTCSR
MCUSR
55

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