ATMEGA48A-MMHR Atmel, ATMEGA48A-MMHR Datasheet - Page 203

• Manufacturer Part Number: ATMEGA48A-MMHR
• Description: IC MCU AVR 4K FLASH 28QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA48A-MMHR

• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Speed: 20MHz
• Number Of I /o: 23
• Eeprom Size: 256 x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 512 x 8
• Program Memory Size: 4KB (4K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8271C–AVR–08/10
• Bits 5:4 – UPMn1:0: Parity Mode
These bits enable and set type of parity generation and check. If enabled, the Transmitter will
automatically generate and send the parity of the transmitted data bits within each frame. The
Receiver will generate a parity value for the incoming data and compare it to the UPMn setting.
If a mismatch is detected, the UPEn Flag in UCSRnA will be set.
Table 19-8.
• Bit 3 – USBSn: Stop Bit Select
This bit selects the number of stop bits to be inserted by the Transmitter. The Receiver ignores
this setting.
Table 19-9.
• Bit 2:1 – UCSZn1:0: Character Size
The UCSZn1:0 bits combined with the UCSZn2 bit in UCSRnB sets the number of data bits
(Character SiZe) in a frame the Receiver and Transmitter use.
Table 19-10. UCSZn Bits Settings
• Bit 0 – UCPOLn: Clock Polarity
This bit is used for synchronous mode only. Write this bit to zero when asynchronous mode is
used. The UCPOLn bit sets the relationship between data output change and data input sample,
and the synchronous clock (XCKn).
ATmega48A/48PA/88A/88PA/168A/168PA/328/328
UCSZn2
UPMn1
0
0
1
1
0
0
0
0
1
1
1
1
UPMn Bits Settings
USBS Bit Settings
USBSn
0
1
UCSZn1
UPMn0
0
1
0
1
0
0
1
1
0
0
1
1
Parity Mode
Disabled
Reserved
Enabled, Even Parity
Enabled, Odd Parity
Stop Bit(s)
1-bit
2-bit
UCSZn0
0
1
0
1
0
1
0
1
Character Size
5-bit
6-bit
7-bit
8-bit
Reserved
Reserved
Reserved
9-bit
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