Datasheet

189
ATtiny828 [DATASHEET]
8371A–AVR–08/12
For more information, see “Start Frame Detection” on page 179.
z Bits 4:0 – Res: Reserved Bits
These bits are reserved and will always read zero.
17.11.6 UBRRL and UBRRH – USART Baud Rate Registers
z Bits 15:12 – Res: Reserved Bits
These bits are reserved for future use. For compatibility with future devices, these bits must be cleared when UBRRH is
written.
z Bits 11:0 – UBRR[11:0]: USART Baud Rate Register
This is a 12-bit register which contains the USART baud rate. UBRRH contains the four most significant bits, and UBRRL
contains the eight least significant bits of the USART baud rate. Ongoing transmissions by the transmitter and receiver
will be corrupted if the baud rate is changed. Writing UBRRL will trigger an immediate update of the baud rate prescaler.
Initial Value 0 0 0 0 0 0 0 0
Read/Write R R R R R/W R/W R/W R/W
Bit 151413121110 9 8
(0xC5) – – – – UBRR[11:8] UBRRH
(0xC4) UBRR[7:0] UBRRL
Bit 76543210
Read/Write R/WR/WR/WR/WR/WR/WR/WR/W
Initial Value 0 0 0 0 0 0 0 0