ATMEGA48-20MMH Atmel, ATMEGA48-20MMH Datasheet - Page 169

• Manufacturer Part Number: ATMEGA48-20MMH
• Description: MCU AVR 4KB FLASH 20MHZ 28QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA48-20MMH

• 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): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Processor Series: ATMEGA48x
• Core: AVR8
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 16 MHz
• Operating Supply Voltage: 2.7 V to 5.5 V
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

18.5.3
2545S–AVR–07/10
SPDR – SPI Data Register
The SPI Data Register is a read/write register used for data transfer between the Register File
and the SPI Shift Register. Writing to the register initiates data transmission. Reading the regis-
ter causes the Shift Register Receive buffer to be read.
Bit
0x2E (0x4E)
Read/Write
Initial Value
MSB
R/W
X
7
R/W
6
X
R/W
X
5
R/W
X
4
R/W
X
3
R/W
ATmega48/88/168
X
2
R/W
1
X
LSB
R/W
X
0
Undefined
SPDR
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