M38203M4 Datasheet, PDF (227/344 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.6 Serial I/O2
2.6 Serial I/O2
2.6.1 Explanation of operations
The operations of the serial I/O2 are described below. The serial I/O2 operates only in the clock synchro-
nous mode. When serial I/O2 is actually used, refer to “2.6.4 Register setting example.”
(1) Clock synchronous serial I/O mode
In the clock synchronous mode, 8 shift clocks generated in the synchronization circuit are used as
synchronizing clocks for transfer. In synchronization with these shift clocks, the transmit operation on
the transmitter and the receive operation on the receiver are simultaneously executed.
The transmitter transmits each 1-bit data from the P51/SOUT2 pin in synchronization with the falling of
the shift clocks.
The receiver receives each 1-bit data from the P50/SIN2 pin in synchronization with the rising of the
shift clocks.
Figure 2.6.1 shows an external connection example of the serial I/O2.
3820 group Œ
XIN
1/8
1/16
1/32
1/64
1/128
1/256
Synchronization ^SCLK2
circuit
3820 group 
SCLK2
Synchronization
circuit
Serial I/O2 register
8
SIN2
SOUT2
SOUT2
SIN2
Serial I/O2 register
8
Internal clock is selected
Fig. 2.6.1 External connection example of serial I/O2
External clock is selected
3820 GROUP USER’S MANUAL
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