m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 296

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

11.4.3 Method of transmission
Figure 11.4.4 shows an initial setting example for relevant registers when transmitting.
The difference depending on the transfer data length (7 bits, 8 bits, or 9 bits) is the transmit data’s length
only. When selecting a 7- or 8-bit data length, be sure to set the transmit data into the low-order byte of
the UARTi transmit buffer register. When selecting a 9-bit data length, be sure to set the transmit data into
the low-order byte and bit 0 of the high-order byte.
Transmission is started when all of the following conditions (
By connecting the RTS
that of reception can be matched. For details, refer to section “11.4.6 Receive operation.”
When using interrupts, it is necessary to set the relevant registers to enable interrupts. For details, refer
to “CHAPTER 6. INTERRUPTS.”
Figure 11.4.5 shows writing data after transmission is started, and Figure 11.4.6 shows detection of
transmit completion.
Note: When the CTS function is not selected, condition
Transmit data is present in the UARTi transmit buffer register (transmit buffer empty flag = “0”).
Transmit is enabled (transmit enable bit = “1”).
The CTS
i
pin’s input level is “L” (when the CTS function selected).
i
pin (receiver side) and CTS
7905 Group User’s Manual Rev.1.0
11.4 Clock asynchronous serial I/O (UART) mode
i
pin (transmitter side), the timing of transmission and
is ignored.
to
) are satisfied:
SERIAL I/O
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