7751 Datasheet, PDF (200/540 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER

SERIAL I/O
7.4 Clock asynchronous serial I/O (UART) mode
[When not using interrupts]
Checking start of transmission
UART0 transmit interrupt control register (Address 7116)
UART1 transmit interrupt control register (Address 7316)
b7
b0
Interrupt request bit
0: No interrupt request
1: Interrupt request
(Transmission has started.)
[When using interrupts]
The UARTi transmit interrupt request
occurs when the transmission starts.
UARTi transmit interrupt
Checking completion of transmission.
UART0 transmit/receive control register 0 (Address 3416)
UART1 transmit/receive control register 0 (Address 3C16)
b7
b0
0
Transmit register empty flag
0: During transmitting
1: Transmitting completed
Note : This figure shows the bits and registers required
for processing.
Refer to Figures 7.4.6 to 7.4.7 about the
change of flag state and the occurrence timing
of an interrupt request.
Processing at completion of transmission
Fig. 7.4.5 Detection of transmission’s completion
7751 Group User’s Manual
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