Section 18 I
2
C Bus Interface (IIC)
Rev. 1.00 Mar. 12, 2008 Page 648 of 1178
REJ09B0403-0100
18.4.9 Noise
Canceler
The logic levels at the SCL and SDA pins are routed through noise cancelers before being latched
internally. Figure 18.28 shows a block diagram of the noise canceler.
The noise canceler consists of two cascaded latches and a match detector. The SCL (or SDA) pin
input signal is sampled on the system clock, but is not passed forward to the next circuit unless the
outputs of both latches agree. If they do not agree, the previous value is held.
System clock
cycle
Sampling clock
C
D
Q
Latch
C
D
Q
Latch
SCL or
SDA input
signal
Match
detector
Internal
SCL or
SDA
signal
Sampling
clock
Figure 18.28 Block Diagram of Noise Canceler
18.4.10 Initialization of Internal State
The IIC has a function for forcible initialization of its internal state if a deadlock occurs during
communication.
Initialization is executed in accordance with clearing ICE bit.
Scope of Initialization:
The initialization executed by this function covers the following items:
•
ICDRE and ICDRF internal flags
•
Transmit/receive sequencer and internal operating clock counter
•
Internal latches for retaining the output state of the SCL and SDA pins (wait, clock, data
output, etc.)
Summary of Contents for H8S Family
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Page 70: ...Section 1 Overview Rev 1 00 Mar 12 2008 Page 22 of 1178 REJ09B0403 0100...
Page 108: ...Section 2 CPU Rev 1 00 Mar 12 2008 Page 60 of 1178 REJ09B0403 0100...
Page 116: ...Section 3 MCU Operating Modes Rev 1 00 Mar 12 2008 Page 68 of 1178 REJ09B0403 0100...
Page 152: ...Section 5 Interrupt Controller Rev 1 00 Mar 12 2008 Page 104 of 1178 REJ09B0403 0100...
Page 206: ...Section 6 Bus Controller BSC Rev 1 00 Mar 12 2008 Page 158 of 1178 REJ09B0403 0100...
Page 420: ...Section 9 14 Bit PWM Timer PWMX Rev 1 00 Mar 12 2008 Page 372 of 1178 REJ09B0403 0100...
Page 476: ...Section 12 Watchdog Timer WDT Rev 1 00 Mar 12 2008 Page 428 of 1178 REJ09B0403 0100...
Page 552: ...Section 14 CRC Operation Circuit CRC Rev 1 00 Mar 12 2008 Page 504 of 1178 REJ09B0403 0100...
Page 712: ...Section 18 I2 C Bus Interface IIC Rev 1 00 Mar 12 2008 Page 664 of 1178 REJ09B0403 0100...
Page 804: ...Section 19 LPC Interface LPC Rev 1 00 Mar 12 2008 Page 756 of 1178 REJ09B0403 0100...
Page 838: ...Section 20 Ethernet Controller EtherC Rev 1 00 Mar 12 2008 Page 790 of 1178 REJ09B0403 0100...
Page 964: ...Section 24 RAM Rev 1 00 Mar 12 2008 Page 916 of 1178 REJ09B0403 0100...
Page 1066: ...Section 25 Flash Memory Rev 1 00 Mar 12 2008 Page 1018 of 1178 REJ09B0403 0100...
Page 1098: ...Section 26 Boundary Scan JTAG Rev 1 00 Mar 12 2008 Page 1050 of 1178 REJ09B0403 0100...
Page 1226: ...Rev 1 00 Mar 12 2008 Page 1178 of 1178 REJ09B0403 0100...
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Page 1230: ...H8S 2472 Group H8S 2462 Group Hardware Manual...