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CHAPTER 20 UART/SIO
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Start bit detection and confirmation of receive data during reception
The start bit is detected by a falling of the serial input followed by a succession of three "L" levels after the
serial data input is sampled according to the clock (BRCLK) signal provided by the dedicated baud rate
generator with the reception operation enable bit (RXE) set to "1". When the first "H, L, L, L" train is
detected in a BRCLK sample, therefore, the current bit is regarded as the start bit.
The frequency-quartered circuit is activated upon detection of the start bit and serial data is inputted to the
reception shift register at intervals of four periods of BRCLK.
When data is received, sampling is performed at three points of the baud rate clock (BRCLK) and data
sampling clock (DSCLK) and received data is confirmed on a majority basis when two bits out of three
match.
Figure 20.7-5 Start Bit Detection and Serial Data Input
Baud rate clock
(BRCLK)
RXE
Counter divided by 4
0
H
D0
X
Reception shift register
L L
L
L
D1
1
2
3
Data sampling clock
(DSCLK)
Serial data input
(UI0)
Start bit detection
0
1
2
3
D0 D1
X
Start bit
Sampling at three points to determine "0" or "1" on a majority basis
when two bits out of three match
Содержание F2 MC-8FX Family
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Страница 30: ...16 CHAPTER 1 DESCRIPTION 1 FPT 64P M23 FPT 64P M24 2 For the I O circuit type refer to 1 8 I O Circuit Type ...
Страница 34: ...20 CHAPTER 1 DESCRIPTION ...
Страница 35: ...21 CHAPTER 2 HANDLING DEVICES This chapter gives notes on using 2 1 Device Handling Precautions ...
Страница 38: ...24 CHAPTER 2 HANDLING DEVICES ...
Страница 39: ...25 CHAPTER 3 MEMORY SPACE This chapter describes memory space 3 1 Memory Space 3 2 Memory Map ...
Страница 43: ...29 CHAPTER 4 MEMORY ACCESS MODE This chapter describes the memory access mode 4 1 Memory Access Mode ...
Страница 56: ...42 CHAPTER 5 CPU ...
Страница 73: ...59 CHAPTER 6 CLOCK CONTROLLER ...
Страница 96: ...82 CHAPTER 6 CLOCK CONTROLLER ...
Страница 104: ...90 CHAPTER 7 RESET ...
Страница 105: ...91 CHAPTER 8 INTERRUPTS This chapter explains the interrupts 8 1 Interrupts ...
Страница 174: ...160 CHAPTER 10 TIMEBASE TIMER ...
Страница 184: ...170 CHAPTER 10 TIMEBASE TIMER ...
Страница 218: ...204 CHAPTER 13 WATCH PRESCALER ...
Страница 257: ...243 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Страница 261: ...247 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Страница 288: ...274 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Страница 301: ...287 CHAPTER 17 16 BIT PPG TIMER ...
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Страница 382: ...368 CHAPTER 21 UART SIO DEDICATED BAUD RATE GENERATOR ...
Страница 390: ...376 CHAPTER 22 I2C ...
Страница 395: ...381 CHAPTER 22 I2C ...
Страница 399: ...385 CHAPTER 22 I2C ...
Страница 430: ...416 CHAPTER 23 10 BIT A D CONVERTER ...
Страница 476: ...462 CHAPTER 24 LCD CONTROLLER ...
Страница 482: ...468 CHAPTER 25 LOW VOLTAGE DETECTION RESET CIRCUIT ...
Страница 494: ...480 CHAPTER 26 CLOCK SUPERVISOR ...
Страница 507: ...493 CHAPTER 27 REAL TIME CLOCK ...
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Страница 532: ...518 CHAPTER 27 REAL TIME CLOCK ...
Страница 536: ...522 CHAPTER 28 256 KBIT FLASH MEMORY ...
Страница 554: ...540 CHAPTER 28 256 KBIT FLASH MEMORY ...
Страница 564: ...550 CHAPTER 29 EXAMPLE OF SERIAL PROGRAMMING CONNECTION ...
Страница 595: ...581 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Страница 596: ...582 INDEX Index ...
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Страница 599: ...585 Pin Function Index V2 LCD power supply driving pin 2 439 V3 LCD power supply driving pin 3 439 ...
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