Datasheet

CHAPTER 14 SERIAL INTERFACE UART6
User’s Manual U18698EJ1V0UD
359
(c) Normal transmission
When bit 7 (POWER6) of asynchronous serial interface operation mode register 6 (ASIM6) is set to 1 and bit
6 (TXE6) of ASIM6 is then set to 1, transmission is enabled. Transmission can be started by writing transmit
data to transmit buffer register 6 (TXB6). The start bit, parity bit, and stop bit are automatically appended to
the data.
When transmission is started, the data in TXB6 is transferred to transmit shift register 6 (TXS6). After that,
the transmit data is sequentially output from TXS6 to the T
XD6 pin. When transmission is completed, the
parity and stop bits set by ASIM6 are appended and a transmission completion interrupt request (INTST6) is
generated.
Transmission is stopped until the data to be transmitted next is written to TXB6.
Figure 14-17 shows the timing of the transmission completion interrupt request (INTST6). This interrupt
occurs as soon as the last stop bit has been output.
Figure 14-17. Normal Transmission Completion Interrupt Request Timing
1. Stop bit length: 1
INTST6
D0Start D1 D2 D6 D7 Stop
T
XD6 (output)
Parity
2. Stop bit length: 2
TXD6 (output)
INTST6
D0Start D1 D2 D6 D7 Parity Stop