CHAPTER 14 ASYNCHRONOUS SERIAL INTERFACE (UART)
User’s Manual U16896EJ2V0UD
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(5) Transmit buffer register n (TXBn)
The TXBn register is an 8-bit buffer register for setting transmit data.
When transmission is enabled (ASIMn.TXEn bit = 1), the transmit operation is started by writing data to TXBn
register.
When transmission is disabled (TXEn bit = 0), even if data is written to the TXBn register, the value is ignored.
The TXBn register data is transferred to the transmit shift register, and a transmission completion interrupt
request signal (INTSTn) is generated, synchronized with the completion of the transmission of one frame
from the transmit shift register. For information about the timing for generating this interrupt request, refer to
14.5.2 Transmit operation
.
When the ASIFn.TXBFn bit = 1, writing must not be performed to the TXBn register.
This register can be read or written in 8-bit units.
Reset sets this register to FFH.
7
TXBn7
TXBn
(n = 0, 1)
6
TXBn6
5
TXBn5
4
TXBn4
3
TXBn3
2
TXBn2
1
TXBn1
0
TXBn0
After reset: FFH R/W Address: TXB0 FFFFFA04H, TXB1 FFFFFA14H
