tmp88fw45afg TOSHIBA Semiconductor CORPORATION, tmp88fw45afg Datasheet - Page 218

• Manufacturer Part Number: tmp88fw45afg
• Description: 8 Bit Microcontroller Tlcs-870/x Series
• Manufacturer: TOSHIBA Semiconductor CORPORATION

17.6
Transfer Mode
17.6
17.6.1
is to be changed during transfer, the serial interface must be stopped before making the change. The number of words
can be changed during automatic-wait operation of an internal clock. In this case, the serial interface is not required
to be stopped.
An INTSIO interrupt is generated when the specified number of words has been transferred. If the number of words
SIOCR1<SIOM> is used to select the transmit, receive, or transmit/receive mode.
Transfer Mode
(number of transfer words to be transferred) to the data buffer registers (DBR).
output sequentially to the SO pin in synchronous with the serial clock, starting with the least significant bit (LSB).
As soon as the LSB has been output, the data are transferred from the data buffer register to the shift register.
When the final data bit has been transferred and the data buffer register is empty, an INTSIO (Buffer empty)
interrupt is generated to request the next transmitted data.
transmitted data are not loaded to the data buffer register by the time the number of data words specified with
the SIOCR2<BUF> has been transmitted. Writing even one word of data cancels the automatic-wait; therefore,
when transmitting two or more words, always write the next word before transmission of the previous word is
completed.
In these modes, firstly set the SIO control register to the transmit mode, and then write first transmit data
After the data are written, the transmission is started by setting SIOCR1<SIOS> to “1”. The data are then
When the internal clock is used, the serial clock will stop and an automatic-wait will be initiated if the next
4-bit and 8-bit transfer modes
SCK pin
SO pin
INTSIO interrupt
SCK pin
SO pin
INTSIO interrupt
SCK pin
SI pin
INTSIO interrupt
Note:Automatic waits are also canceled by writing to a DBR not being used as a transmit data buffer register;
Figure 17-6 Number of words to transfer (Example: 1word = 4bit)
therefore, during SIO do not use such DBR for other applications. For example, when 3 words are trans-
mitted, do not use the DBR of the remained 5 words.
a
a
a
0
0
0
a
a
a
1
1
1
a
a
a
2
2
2
Page 204
a
a
3
3
(b) 3 words transmit
(a) 1 word transmit
(c) 3 words receive
b
b
0
0
a
3
b
b
1
1
b
b
2
2
b
b
3
3
c
c
0
0
c
c
1
1
c
c
2
2
c
c
3
3
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