M38203M4 Datasheet, PDF (220/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.5 Serial I/O1
Continued from Figure 2.5.22
Setting of UART control register
b7
b0
UARTCON: UART control register [Address 1B16]
b0: Character length selection bit
0: 8 bits
1: 7 bits
b1: Parity enable bit
0: Parity checking disabled
1: Parity checking enabled
b2: Parity selection bit
0: Even parity
1: Odd parity
b3: Stop bit length selection bit
0: 1 stop bit
1: 2 stop bits
b4: P45/TxD P-channel output disable bit
0: CMOS output (in output mode)
1: N-channel open-drain output (in output mode)
: Nothing is allocated
Set the serial I/O1 transmit interrupt request to “0”
(Allow an interval of one or more instructions after Ž)
b7
b0
0
IREQ1: Interrupt request register 1 [Address 3C16]
b3: Serial I/O1 transmit interrupt request bit
0: No interrupt request issued
‘Enable serial I/O1 transmit interrupt
b7
b0
1
ICON1: Interrupt control register 1 [Address 3E16]
b3: Serial I/O1 transmit interrupt enable bit
1: Interrupts enabled
’Set transmit data to transmit buffer register (TB) [Address 1816]
“Processing of serial I/O1 transmit interrupt
Fig. 2.5.23 Transmitting method in UART mode (2)
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3820 GROUP USER’S MANUAL