Technical information
26
3886 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
SERIAL I/O
Serial I/O1
Serial I/O1 can be used as either clock synchronous or asynchro-
nous (UART) serial I/O. A dedicated timer is also provided for
baud rate generation.
(1) Clock Synchronous Serial I/O Mode
Clock synchronous serial I/O1 mode can be selected by setting
the serial I/O1 mode selection bit of the serial I/O1 control register
(bit 6 of address 001A16) to “1”.
For clock synchronous serial I/O, the transmitter and the receiver
must use the same clock. If an internal clock is used, transfer is
started by a write signal to the TB/RB.
Fig. 21 Block diagram of clock synchronous serial I/O1
Fig. 22 Operation of clock synchronous serial I/O1 function
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