ATMEGA8_14 Datasheet, PDF (310/331 Pages) ATMEL Corporation – High-performance, Low-power Atmel

ATmega8(L)
Register Summary (Continued)
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Page
0x01 (0x21)
TWSR
TWS7
TWS6
TWS5
TWS4
TWS3
–
TWPS1
TWPS0
166
0x00 (0x20)
TWBR
Two-wire Serial Interface Bit Rate Register
165
Notes:
1. Refer to the USART description (“USART” on page 129) for details on how to access UBRRH and UCSRC (“Accessing
UBRRH/UCSRC Registers” on page 146)
2. For compatibility with future devices, reserved bits should be written to zero if accessed. Reserved I/O memory addresses
should never be written
3. Some of the Status Flags are cleared by writing a logical one to them. Note that the CBI and SBI instructions will operate on
all bits in the I/O Register, writing a one back into any flag read as set, thus clearing the flag. The CBI and SBI instructions
work with registers 0x00 to 0x1F only
2486AA–AVR–02/2013
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