UART definitions

Hi, i am wondering where in the arduino header files all the UART stuff is defined,

I need the definitions for TXB8, TXB81 usw for serial communication

greetings Tarcontar

Hi, i am wondering where in the arduino header files all the UART stuff is defined,

For which Arduino? The AVR Arduinos define then in different places from the ARM Arduinos.

I need the definitions for TXB8, TXB81 usw for serial communication

Why?

If the board is set correctly, you get the standard AVR definitions included for the appropriate microcontroller.
boards.txt is the place to look.

the arduino mega 2560,
i am doing custom UART serial and the TXB8 usw ist not defined if i do so,
but i dont want it on Serial 0 but on Serial 1 or so, so I need the register definitions for TXB81 and so on

hardware/tools/avr/avr/include/avr/io.h

That file includes the right file for the AVR processor selected. For example: for the ATmega2560 it includes: hardware/tools/avr/avr/include/avr/iom2560.h which includes hardware/tools/avr/avr/include/avr/iomxx0_1.h which defines TXB80, TXB81, TXB82, and TXB83 (all defined as 0 because it is bit 0 of the UCSRnB register).

If you are getting errors using TXB81 then you may have selected the wrong board/processor. The datasheet DOES talk about 'TXB8' but it should probably have said 'TXB8n'.

thx that was what I was looking for