25.5.4 Transmit Data Register High Byte

USARTn.TXDATAH holds the ninth data bit in the character to be transmitted when operating with serial frames with nine data bits. When used this bit must be written before writing to USARTn.TXDATAL except if CHSIZE in USARTn.CTRLC is set to 9BIT Low byte first where USARTn.TXDATAL should be written first.

This bit is unused in Master SPI mode of operation.

Name: TXDATAH
Offset: 0x03
Reset: 0x00
Property: -

Bit 76543210 
        DATA[8] 
Access W 
Reset 0 

Bit 0 – DATA[8] Transmit Data Register

This bit is used when CHSIZE=9BIT in USARTn.CTRLC.