M38203M4 Datasheet, PDF (210/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.5 Serial I/O1
(3) Serial I/O1 control register (SIO1CON)
This register (address 001A16) controls various functions related to the serial I/O1, such as transmit/
receive modes, clocks, and pin functions. All the bits of this register are read and written by software.
Serial I/O1 control register
b7 b6 b5 b4 b3 b2 b1 b0
Serial I/O1 control register (SIO1CON) [Address 1A16]
B
Name
Functions
0 BRG count source ^{0: f(XIN)}
selection bit (CSS) 1: f(XIN)/4
1 Serial I/O1
•In clock synchronous mode
synchronization clock 0: BRG output/4
selection bit
1: External clock input
(SCS)
•In UART mode
0: BRG output/16
1: External clock input/16
At reset R W
0
0
2 ^SRDY1 output enable ^{0: P47/SRDY1 pin operates as I/O port P47}
0
bit (SRDY)
1: P47/SRDY1 pin operates as signal output
pin SRDY1
(SRDY1 signal indicates receive enable state)
3 Transmit interrupt 0: When transmit buffer has emptied
0
source selection
1: When transmit shift operation is
bit (TIC)
completed
4 Transmit enable bit ^{0: Transmit disabled}
0
(TE)
1: Transmit enabled
5 Receive enable bit ^{0: Receive disabled}
0
(RE)
1: Receive enabled
6 Serial I/O1 mode
0: Clock asynchronous serial I/O1 (UART)
0
selection bit (SIOM) mode
1: Clock synchronous serial I/O1 mode
7 Serial I/O1 enable bit 0: Serial I/O1 disabled
0
(SIOE)
(pins P44–P47 operate as I/O pins)
1: Serial I/O1 enabled
(pins P44–P47 operate as serial I/O1 pins)
Fig. 2.5.16 Structure of serial I/O1 control register
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3820 GROUP USER’S MANUAL