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CHAPTER 22 SERIAL I/O
22.1
Outline of Serial I/O
The serial I/O interface operates in two modes:
• Internal shift clock mode: Data is transferred in synchronization with the internal
clock.
• External shift clock mode: Data is transferred in synchronization with the clock
supplied via the external pin (SCK4). By manipulating the
general-purpose port sharing the external pin (SCK4), data
can also be transferred by a CPU instruction in this mode.
■
Serial I/O Block Diagram
This block is a serial I/O interface that allows data transfer using clock synchronization. The interface
consists of a single eight-bit channel. Data can be transferred from the LSB first or MSB first.
Figure 22.1-1 Extended Serial I/O Interface Block Diagram
SIN3
SOT3
SCK3
2
1
0
SMD2
Internal data bus
(MSB first) D7 to D0
D7 to D0 (LSB first)
Transfer direction selection
SDR (Serial data register)
Read
Write
Control circuit
Internal clock
Interrupt
Internal data bus
request
Shift clock counter
SMD1
SMD0
SIE
SIR
BUSY
STOP
STRT MODE
BDS
SOE
SCOE
SIN4
SOT4
SCK4
Summary of Contents for MB90390 Series
Page 2: ......
Page 4: ......
Page 17: ...xiii APPENDIX D List of Interrupt Vectors 690 INDEX 695 ...
Page 18: ...xiv ...
Page 132: ...104 CHAPTER 5 CLOCKS ...
Page 152: ...124 CHAPTER 6 CLOCK MODULATOR ...
Page 210: ...182 CHAPTER 11 TIME BASE TIMER ...
Page 218: ...190 CHAPTER 12 WATCHDOG TIMER ...
Page 264: ...236 CHAPTER 14 16 BIT RELOAD TIMER WITH EVENT COUNT FUNCTION ...
Page 274: ...246 CHAPTER 15 WATCH TIMER ...
Page 306: ...278 CHAPTER 17 DTP EXTERNAL INTERRUPTS ...
Page 338: ...310 CHAPTER 18 8 10 BIT A D CONVERTER ...
Page 364: ...336 CHAPTER 19 UART0 UART1 ...
Page 398: ...370 CHAPTER 20 UART2 UART3 Figure 20 5 2 ORE Set Timing Receive data RDRF ORE ...
Page 432: ...404 CHAPTER 20 UART2 UART3 ...
Page 482: ...454 CHAPTER 22 SERIAL I O ...
Page 560: ...532 CHAPTER 24 STEPPING MOTOR CONTROLLER ...
Page 582: ...554 CHAPTER 27 ROM MIRRORING MODULE ...
Page 632: ...604 CHAPTER 29 EXAMPLES OF SERIAL PROGRAMMING CONNECTION ...
Page 722: ...694 APPENDIX ...
Page 723: ...695 INDEX The index follows on the next page This is listed in alphabetic order ...
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