m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 279

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

SERIAL I/O
11.3 Clock synchronous serial I/O mode
11-24
11.3.3 Method of transmission
Figure 11.3.2 shows an initial setting example for relevant registers when transmitting. Transmission is
started when all of the following conditions (
satisfy conditions
<Preconditions>
The CLK
The CLK
Note: When an internal clock is selected, the above preconditions are ignored.
By connecting the RTS
that of reception can be matched. For details, refer to section “11.3.6 Receive operation.”
When using interrupts, it is necessary to set the relevant registers to enable interrupts. For details, refer
to “CHAPTER 6. INTERRUPTS.”
Figure 11.3.3 shows the write operation of data after transmission start, and Figure 11.3.4 shows the detect
operation of transmit completion.
Transmit data is present in the UARTi transmit buffer register (transmit buffer empty flag = “0”)
Transmission is enabled (transmit enable bit = “1”).
The CTS
Note: When the CTS function is not selected, condition
i
i
pin’s input is at “H” level (External clock selected, when the CLK polarity select bit = “0”)
pin’s input is at “L” level (External clock selected, when the CLK polarity select bit = “1”)
i
pin’s input is at “L” level (when the CTS function selected).
to
i
pin (receiver side) and CTS
with the following preconditions satisfied.
7905 Group User’s Manual Rev.1.0
to
) has been satisfied. When an external clock is selected,
i
pin (transmitter side), the timing of transmission and
is ignored.