Fujitsu F2MC-8L F202RA Hardware Manual page 337

Table 14.4-1 Explanation of Functions of Each Bit in Serial Mode Register (SMR) (1/2)
Bit name
SIOF:
bit7
Interrupt request flag bit
SIOE:
bit6 Interrupt request
allowance bit
SCKE:
bit5 Shift clock output
allowance bit
SOE:
bit4 Serial data output
allowance bit
bit3, CKS1, CKS0:
bit2 Shift clock selection bits
• When 8-bit serial data is input or output during serial I/O operation, this
bit is set to "1". When this bit and the interrupt request allowance bit
(SIOE) are "1", an interrupt request is output.
• Setting this bit to "0" clears it, while setting it to "1" does not affect this
bit or implement any changes.
This bit is used to allow and prohibit interrupt request output to the CPU.
When this bit and the interrupt request allowance bit (SIOF) are "1", an
interrupt request is output.
• This bit is used to control shift clock I/O.
• When this bit is "0", the P30/UCK/SCK pin functions as the shift clock
input pin. When "1", it functions as the shift clock output pin.
Notes:
• To use the P30/UCK/SCK pin as the shift clock input pin, it must be set
as an input port. Also select the external shift clock with the shift clock
selection bits (Set the CKS1 and CKS0 bits to 11
• For shift clock output (SCKE bit = 1), select an internal shift clock (do
not set the CKS1 and CKS0 bits to 11
Notes:
• When shift clock output is allowed (when this bit is "1"), the P30/UCK/
SCK pin functions as the UCK/SCK output pin irrespective of the
general-purpose port (P30) state.
• When using the P30/UCK/SCK pin as a general-purpose port (P30), set
its pin as the shift clock input pin (set this bit to "0").
When this bit is "0" the P31/UO/SO pin functions as a general-purpose port
(P31). When "1", the P31/UO/SO pin functions as the serial data output pin
(UO/SO).
Note:
When serial data output is allowed (when this bit is set to "1"), the P31/
UO/SO pin functions as the UO/SO pin irrespective of the general-
purpose port (P31) state.
• These bits are used to select three internal shift clocks or one external
shift clock.
• When these bits are not 11
shift clock output allowance bit (SCKE) is "1", a shift clock is output
from the UCK/SCK pin.
• When these bits are 11
UCK/SCK pin is set as the shift clock input pin, a shift clock is input
from the UCK/SCK pin (when the SCKE bit and bit0 of the DDR3 are
"0").
CHAPTER 14 8-BIT SERIAL I/O
Function
).
B
, an internal shift clock is selected. When the
B
, the external clock is selected. When the P30/
B
).
B
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