M38002M4 Datasheet, PDF (91/173 Pages) Mitsubishi Electric Semiconductor – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.3 Serial I/O
(4) Communication (transmit/receive) using an asynchronous serial I/O (UART)
Point : 2-byte data is transmitted and received through an asynchronous serial I/O.
The port P40 is used for communication control.
Figure 2.3.29 shows a connection diagram, and Figure 2.3.30 shows a timing chart.
Transmitting side
P40
TXD
3800 group
Receiving side
P40
RXD
3800 group
Fig. 2.3.29 Connection diagram [Communication using UART]
Specifications :
• The Serial I/O is used (UART is selected).
• Transfer bit rate : 9600 bps (f(XIN) = 4.9152 MHz is divided by 512)
• Communication control using port P40
(The output level of the port P40 is controlled by softoware.)
• 2-byte data is transferred from the transmitting side to the receiving side at inter-
vals of 10 ms (generated by timer).
P40
TXD
ST D0 D1 D2 D3 D4 D5 D6 D7 SP(2) ST D0 D1 D2 D3 D4 D5 D6 D7 SP(2)
10 ms
ST D0
Fig. 2.3.30 Timing chart [Communication using UART]
3800 GROUP USER’S MANUAL
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