tmp88f846ug TOSHIBA Semiconductor CORPORATION, tmp88f846ug Datasheet - Page 177

• Manufacturer Part Number: tmp88f846ug
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

DBR
SIOCR1<SIOS>
SIOSR<SIOF>
SIOSR<SEF>
SCK pin
(Output)
SI pin
INTSIO Interrupt
16.6.3 8-bit transfer / receive mode
Figure 16-10 Receive Mode (Example: 8bit, 1word transfer, Internal clock)
to the data buffer registers (DBR). After that, enable the transmit/receive by setting SIOCR1<SIOS> to “1”.
When transmitting, the data are output from the SO pin at leading edges of the serial clock. When receiving,
the data are input to the SI pin at the trailing edges of the serial clock. When the all receive is enabled, 8-bit
data are transferred from the shift register to the data buffer register. An INTSIO interrupt is generated when
the number of data words specified with the SIOCR2<BUF> has been transferred. Usually, read the receive
data from the buffer register in the interrupt service. The data buffer register is used for both transmitting and
receiving; therefore, always write the data to be transmitted after reading the all received data.
are written. A wait will not be initiated if even one transfer data word has been written.
necessary to read the received data and write the data to be transmitted next before starting the next shift oper-
ation. When an external clock is used, the transfer speed is determined by the maximum delay between genera-
tion of an interrupt request and the received data are read and the data to be transmitted next are written.
The transmit/receive operation is ended by clearing SIOCR1<SIOS> to “0” or setting SIOCR1<SIOINH> to
“1” in INTSIO interrupt service program.
cleared, the transmitting/receiving is ended at the time that the final bit of the data has been transmitted.
SIOSR<SIOF> is cleared to “0” when the transmitting/receiving is ended.
cleared to “0”.
cleared to “0”, then SIOCR2<BUF> must be rewritten after confirming that SIOSR<SIOF> has been cleared to
“0”.
occurs after completion of transmit/receive operation, SIOCR2<BUF> must be rewritten before reading and
writing of the receive/transmit data.
After setting the SIO control register to the 8-bit transmit/receive mode, write the data to be transmitted first
When the internal clock is used, a wait is initiated until the received data are read and the next transfer data
When an external clock is used, the shift operation is synchronized with the external clock; therefore, it is
When SIOCR1<SIOS> is cleared, the current data are transferred to the buffer. After SIOCR1<SIOS>
When SIOCR1<SIOINH> is set, the transmit/receive operation is immediately ended and SIOSR<SIOF> is
If it is necessary to change the number of words in external clock operation, SIOCR1<SIOS> should be
If it is necessary to change the number of words in internal clock, during automatic-wait operation which
That the transmitting/receiving has ended can be determined from the status of SIOSR<SIOF>.
a
0
a
1
a
2
a
3
a
4
Page 167
a
5
a
6
a
7
Read out
a
b
0
b
1
b
2
Clear SIOS
b
3
b
4
b
5
TMP88F846UG
b
6
b
Read out
7
b