ATMEGA169 ATMEL [ATMEL Corporation], ATMEGA169 Datasheet - Page 173

• Manufacturer Part Number: ATMEGA169
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

USART Control and Status
Register C – UCSRC
2514P–AVR–07/06
• Bit 6 – UMSEL: USART Mode Select
This bit selects between asynchronous and synchronous mode of operation.
Table 74. UMSEL Bit Settings
• Bit 5:4 – UPM1:0: Parity Mode
These bits enable and set type of parity generation and check. If enabled, the Transmit-
ter 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 com-
pare it to the UPM0 setting. If a mismatch is detected, the UPE Flag in UCSRA will be
set.
Table 75. UPM Bits Settings
• Bit 3 – USBS: Stop Bit Select
This bit selects the number of stop bits to be inserted by the Transmitter. The Receiver
ignores this setting.
Table 76. USBS Bit Settings
Bit
Read/Write
Initial Value
UPM1
UMSEL
0
0
1
1
0
1
USBS
R
7
–
0
0
1
UMSEL
R/W
6
0
UPM0
Mode
Asynchronous Operation
Synchronous Operation
0
1
0
1
UPM1
R/W
5
0
Stop Bit(s)
1-bit
2-bit
UPM0
R/W
Parity Mode
Disabled
Reserved
Enabled, Even Parity
Enabled, Odd Parity
4
0
USBS
R/W
3
0
UCSZ1
R/W
2
1
ATmega169/V
UCSZ0
R/W
1
1
UCPOL
R/W
0
0
UCSRC
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