Outline Of Extended I/O Serial Interface - Fujitsu F2MC-16LX Hardware Manual

CHAPTER 20 EXTENDED I/O SERIAL INTERFACE
20.1

Outline of Extended I/O Serial Interface

The extended I/O serial interface is a serial I/O interface that can transfer data through
the adoption of 8-bit × 1 channel configured clock synchronization scheme. LSB first/
MSB first can be selected in data transfer.
Outline of Extended I/O Serial Interface
The following two operation modes are available for the extended I/O serial interface.
• Internal shift clock mode: Transfers data in sync with the internal clock.
• External shift clock mode: Transfers data in sync with the clock input through an external pin (SCK). In
Block Diagram in Extended I/O Serial Interface
Figure 20.1-1 shows the block diagram of extended I/O serial interface.
(MSB first) D0 to D7
SIN
SOT
SCK
Internal clock
460
this mode, transfer operation performed by the CPU instruction is also
available by operating the general-use port sharing an external pin (SCK).
Figure 20.1-1 Block Diagram of Extended I/O Serial Interface
Internal data bus
SDR (Serial data register)
Control circuit
2 1 0
SMD2 SMD1 SMD0 SIE
Internal data bus
D7 to D0 (LSB first)
Transfer direction selection
Shift clock counter
SIR BUSY STOP STRT MODE BDS SOE SCOE
Interrupt
request
#38
Initial value
Read
Write
SMCS