tmp89fm42 TOSHIBA Semiconductor CORPORATION, tmp89fm42 Datasheet - Page 259

• Manufacturer Part Number: tmp89fm42
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

RA001
17.5 Transfer Modes
17.5.1 8-bit transmit mode
17.5.1.1 Setting
17.5.1.2 Starting the transmit operation
17.5.1.3 Transmit buffer and shift operation
17.5.1.4 Operation on completion of transmission
The 8-bit transmit mode is selected by setting SIO0CR<SIOM> to "01".
at SIO0CR<SIODIR> and a serial clock at SIO0CR<SIOCKS>. To use the internal clock as the serial
clock, select an appropriate serial clock at SIO0CR<SIOCKS>. To use an external clock as the serial
clock, set SIO0CR<SIOCKS> to "111".
SIO0CR<SIOS> to "1".
in progress, or when SIO0SR<SIOF> is "1". Make these settings while the serial communication is
stopped. While the serial communication is in progress (SIO0SR<SIOF>="1"), only writing "00" to
SIO0CR<SIOM> or writing "0" to SIO0CR<SIOS> is valid.
The transmit data is transferred from SIO0BUF to the shift register, and then transmitted as the serial data
from the SO0 pin according to the settings of SIO0CR<SIOEDG, SIOCKS and SIODIR>. The serial data
becomes undefined if the transmit operation is started without writing any transmit data to SIO0BUF.
In the external clock operation, an external clock must be supplied to the SCLK0 pin.
INTSIO0 interrupt request is generated.
empty, the written data is transferred to the shift register immediately. At this time, SIO0SR<TBFL>
remains at "0".
"1". If new data is written to SIO0BUF in this state, the contents of SIO0BUF are overwritten by the new
value. Make sure that SIO0SR<TBFL> is "0" before writing data to SIO0BUF.
state of SIO0SR<TBFL>.
Before starting the transmit operation, select the transfer edges at SIO0CR<SIOEDG>, a transfer format
The 8-bit transmit mode is selected by setting SIO0CR<SIOM> to "01".
The transmit operation is started by writing the first byte of transmit data to SIO0BUF and then setting
Writing data to SIO0CR<SIOEDG, SIOCKS and SIODIR> is invalid when the serial communication is
The transmit operation is started by writing data to SIO0BUF and then setting SIO0CR<SIOS> to "1".
In the internal clock operation, the serial clock of the selected baud rate is output from the SCLK0 pin.
By setting SIO0CR<SIOS> to "1", SIO0SR<SIOF and SEF> are automatically set to "1" and an
SIO0SR<SEF> is cleared to "0" when the 8th bit of the serial data is output.
If data is written to SIO0BUF when the serial communication is in progress and the shift register is
If data is written to SIO0BUF when some data remains in the shift register, SIO0SR<TBFL> is set to
The operation on completion of the data transmission varies depending on the operating clock and the
Page 245
TMP89FM42