R8C33A Datasheet, PDF (376/617 Pages) Renesas Technology Corp – MCU M16C FAMILY / R8C/Tiny SERIES

Under development ^{Preliminary specification}
Specifications in this manual are tentative and subject to change.
R8C/33A Group
22. Serial Interface (UART2)
22.5.1 Detection of Start and Stop Conditions
Whether a start or a stop condition has been detected is determined.
A start condition detect interrupt request is generated when the SDA2 pin changes state from high to low while
the SCL2 pin is in the high state. A stop condition detect interrupt request is generated when the SDA2 pin
changes state from low to high while the SCL2 pin is in the high state.
Because the start and stop condition detect interrupts share an interrupt control register and vector, check the
BBS bit in the U2SMR register to determine which interrupt source is requesting the interrupt.
Figure 22.15 shows the Detection of Start and Stop Conditions.
5 cycles of f1 < Setting up duration
5 cycles of f1 < Holding duration
SCL2
SDA2
(Start condition)
Setting up
duration
SDA2
(Stop condition)
Figure 22.15 Detection of Start and Stop Conditions
Holding
duration
REJ09B0455-0010 Rev.0.10 Feb 29, 2008
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