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Rev. 1.21
128
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Rev. 1.21
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HT66F488/HT66F489
A/D Flash MCU with EEPROM
HT66F488/HT66F489
A/D Flash MCU with EEPROM
I
2
C Bus ISR Flow Chart
I
2
C Time-out Control
In order to reduce the I
2
C lockup problem due to reception of erroneous clock sources, a time-out
function is provided. If the clock source connected to the I
2
C bus is not received for a while, then the
I
2
C circuitry and registers will be reset after a certain time-out period. The time-out counter starts
to count on an I
2
C bus “START” & “address match” condition, and is cleared by an SCL falling
edge. Before the next SCL falling edge arrives, if the time elapsed is greater than the time-out period
specified by the
SIM
TOC register, then a time-out condition will occur. The time-out function will
stop when an I
2
C “STOP” condition occurs.