CHAPTER 11 SERIAL INTERFACE FUNCTION
User’s Manual U15109EJ3V0UD
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Transmission/reception of data is performed by the SIOn register (n = 0, 1).
(1) Serial I/O shift register n (SIOn)
The SIOn register is a 16-bit shift register that converts parallel data into serial data, and is used for both
transmission and reception.
Data is shifted in (reception) and shifted out (transmission) from the MSB or LSB side.
The actual transmit/receive operations are started up by accessing the buffer register.
Remark
n = 5, 6
(2) Serial I/O shift register Ln (SIOLn)
The SIOLn register is an 8-bit shift register that converts parallel data into serial data, and is used for both
transmission and reception.
Data is shifted in (reception) and shifted out (transmission) from the MSB or LSB side.
The actual transmit/receive operations are started up by accessing the buffer register.
Remark
n = 5, 6
(3) Selector
The selector selects the serial clock to be used.
(4) Serial clock controller
The serial clock controller controls the serial clock supply to the shift register, as well as the clock output to the
SCKn pin when the internal clock is used.
(5) Serial clock counter
The serial clock counter counts the serial clock output or input during transmission/reception, and checks
whether 8-bit or 16-bit data transmission/reception has been performed.
(6) Interrupt controller
The interrupt controller controls the interrupt request timing.