Fujitsu MB91191 Manuel D’Utilisation
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CHAPTER 17 Serial I/O
17.1
Overview of Serial I/O
The serial I/O can automatically transfer 8-bit serial data and can select external
initiation, multiple shift clock, and transfer interval time.
initiation, multiple shift clock, and transfer interval time.
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Feature of Serial I/O
•
8-bit serial data can be transferred using clock synchronization.
•
Automatic transfer of up to 128 bytes
•
External initiation by ship select input (XCS)
•
4-type shift clock (inner: 3, outer: 1) can be selected
•
Enable/disable of transition interval time can be selected
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Block Diagram of Serial I/O
Figure 17.1-1 Block diagram of serial I/O
Internal Bus
SIF
ICLR
SIE
CSAF ACLR
DIR
CSE
ST
BM
Transfer Byte Count Register
Transfer Byte Count Register
Control Unit
IC1
IC0
SC2
SC1
SC0
IC0
SC2
SC1
SC0
Compare
Address offset
Shift Register
Clock
Control
Unit
Control
Unit
XCS
SCK
SCK
2
3
/fch
2
4
/fch
2
5
/fch
External
SO
SI
Port
CTL
IRQx
R
BMOD
RAM
M
P
X
X
SHIFT-CLOCK