CHAPTER 11 SERIAL INTERFACE FUNCTION
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User’s Manual U14359EJ4V0UM
(5) Transmit buffer registers 0 to 2 (TXB0 to TXB2)
These are 8-bit buffer registers for setting transmit data.
When transmission is enabled (TXEn = 1 in the ASIMn register), the transmit operation is started by writing
data to TXBn.
When transmission is disabled (TXEn = 0 in the ASIMn register), even if data is written to TXBn, the value is
ignored.
The TXBn data is transferred to the transmit shift register, and a transmission completion interrupt request
(INTSTn) is generated, in synchronization with the completion of the transmission of one frame from the
transmit shift register. For information about the timing for generating these interrupt requests, see
11.2.5 (2)
Transmit operation
.
When TXBFn = 1 in the ASIFn register, writing must not be performed to TXBn.
These registers can be read or written in 8-bit units.
Remark
n = 0 to 2
7
6
5
4
3
2
1
0
Address
After reset
TXB0
TXB07
TXB06
TXB05
TXB04
TXB03
TXB02
TXB01
TXB00
FFFFFA04H
FFH
TXB1
TXB17
TXB16
TXB15
TXB14
TXB13
TXB12
TXB11
TXB10
FFFFFA14H
FFH
TXB2
TXB27
TXB26
TXB25
TXB24
TXB23
TXB22
TXB21
TXB20
FFFFFA24H
FFH
Bit position
Bit name
Function
7 to 0
TXBn7 to
TXBn0
(n = 0 to 2)
Transmit Buffer
Writes transmit data.