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R01UH0336EJ0102 Rev.1.02
Page 1221 of 1538
Jul 17, 2014
V850E2/PG4-L
Section 22 Synchronous/Asynchronous Serial Interface H (UARTH)
5
URTHnBTT
BF transmission trigger
0: The value read is always 0. Writing 0 is ignored.
1: Triggers BF transmission.
•
Writing 1 to this bit while URTHnSTR0.URTHnSSBT = 0 and transmission is
enabled (URTHnSTR1.URTHnDCE = 0) causes a BF transmission request to
be issued and URTHnSTR0.URTHnSSBT to be set to 1.
•
Writing 1 to this bit during data transmission leads to the transmission of a BF
after the transmission in progress is completed. Even if 1 is again written to
this bit before BF transmission is completed, the BF will only be transmitted
once.
•
When transmission is enabled (URTHnCTL0.URTHnPW =
URTHnCTL0.URTHnTXE = 1), writing 1 to this bit clears all previously set
data transmission requests (for which the data have not been transmitted),
leaving only any BF transmission request. If a new value is written to the
URTHnTX.URTHnTX[7:0] bits after 1 is written to this bit, the data are
transmitted after the BF.
•
If both a BF transmit request and a data transmit request have been set when
a transmission starts, the BF transmission takes priority.
•
When URTHnSTR1.URTHnDCE = 1, writing 1 to this bit is ignored.
•
Setting this bit is only allowed when transmission is enabled
(URTHnCTL0.URTHnPW = 1, URTHnCTL0.URTHnTXE = 1).
Table 22-11
URTHnTRG Register Contents (2/2)
Bit Position
Bit Name
Function