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C
U
4
Receive-Only Mode
Reading starts reception
Storing up to the (N
2)th data (other
than the last two)
When reception is complete, read the
received data from this register. Repeat
this operation until the (N
2)th data has
been received.
(Supplement)
Do not read the (N
1)th data from this
register. If read, a reception operation
starts and continuous transfer cannot be
completed.
Storing the (N
1)th received data
Read the (N
1)th received data from
this register when the (N
1)th or Nth
(last) data has been received.
Note 2
Storing the Nth (last) received data
Note 2
When the Nth (last) data has been
received, read the Nth (last) data.
Not used
Not used
Continuous Transfer
Note 1
Transmission/Reception Mode
Storing up to the (N
1)th received data
(other than the last)
Note 2
When reception is complete, read the
received data from this register. Repeat
this operation until the (N
1)th data has
been received.
Not used
Storing the Nth (last) received data
Note 2
When the Nth (last)
transmission/reception is complete, read
the Nth (last) data.
Starting transmission/reception when
written
Storing the data to be transmitted
second and subsequently
When transmission/reception is
complete, write the data to be
transmitted next to this register to start
the next transmission/reception.
Storing the data to be transmitted first
Note 2
Before starting transmission/reception
(writing to SOTBn), write the data to be
transmitted first.
Receive-Only Mode
Reading starts reception
Storing received data
First, read dummy data and start
transfer.
To perform reception of the next data
after reception is complete, read the
received data from this register.
Storing the data received last
Note 2
If reception of the next data will not be
performed after reception is complete,
read the received data from this register.
Not used
Not used
Not used
Single Transfer
Transmission/Reception Mode
Storing received data
Note 2
When transmission and reception are
complete, read the received data from
this register.
Not used.
Not used.
Starting transmission/reception when
written
Storing the data to be transmitted
First, write a dummy data (FFH) to start
transmission/reception.
When transmission/reception is
complete, write the data to be
transmitted next.
Not used
Function
Use method
Function
Use method
Function
Use method
Function
Use method
Function
Use method
R/W
Read
Read
Read
Write
Write
Table 17-1. Use of Each Buffer Register
Register
Name
SIRBn
(SIRBnL)
SIRBEn
(SIRBEnL)
SIO0n
(SIO0nL)
SOTBn
(SOTBnL)
SOTBFn
(SOTBFnL)
Notes 1.
It is assumed that the number of data to be transmitted is N.
2.
Neither reading nor writing will start communication.
Remark
In the 16-bit mode, the registers not enclosed in parentheses are used; in the 8-bit mode, the registers in parentheses are used.