M38002M4 Datasheet, PDF (94/173 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.3 Serial I/O
Receiving side
Serial I/O status register (Address : 1916)
b7
b0
SIOSTS
Receive buffer full flag
Check a completion of receiving 1-byte data with this flag.
“1” : at completing to receive
“0” : at reading out a content of the Receive buffer register
Overrun error flag
“1” : when data are ready to be transferred to the Receive
shift register in the state of storing data into the Receive
buffer register.
Parity error flag
“1” : when parity error occurs at enabled parity.
Framing error flag
“1” : when data can not be received at the timing of setting
a stop bit.
Summing error flag
“1” : when even one of the following errors occurs.
• Overrun error
• Parity error
• Framing error
Serial I/O control register (Address : 1A16)
b7
b0
SIOCON _{1 0 1 0 0 0 1}
BRG count source selection bit : f(XIN)/4
Serial I/O synchronous clock selection bit : BRG/16
SRDY output enable bit : Not use SRDY out
Transmit enable bit : Transmit disabled
Receive enable bit : Receive enabled
Serial I/O mode selection bit : Asynchronous serial I/O(UART)
Serial I/O enable bit : Serial I/O enabled
UART control register (Address : 1B16)
b7
b0
UARTCON
1
00
Character length selection bit : 8 bits
Parity enable bit : Parity checking disabled
Stop bit length selection bit : 2 stop bits
Baud rate generator (Address : 1C16)
b7
BRG
b0
f(XIN)
7
Set
–1
Transfer bit rate ! 16 ! m ^T
T ^{when bit 0 of the Serial I/O control register (Address : 1A16) is set to “0,”}
a value of m is 1.
when bit 0 of the Serial I/O control register (Address : 1A16) is set to “1,”
a value of m is 4.
Fig. 2.3.32 Setting of related registers at a receiving side [Communication using UART]
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3800 GROUP USER’S MANUAL