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3. To set SBI0CR2<PIN> to "1", write a dummy data (0x00) to SBI0DBR.
Transfer 1-bit data by setting SBI0CR1<PIN> to "1".
In this case, since the master device is a receiver, the SDA line on a bus keeps the high level. The
transmitter receives the high-level signal as a negative acknowledge signal. The receiver indicates to
the transmitter that data transfer is complete.
After 1-bit data is received and an interrupt request has occurred, generate the stop condition to
terminate data transfer.
Negative
acknowledge signal
to the transmitter
After reading the received data, clear
SBI0CR1<ACK> to "0" and writing the
dummy data (0x00)
SCL0 pin
SDA0 pin
SBI0CR<PIN>
INTSBI0 Interrupt
request
After reading the reveived
data, set SBI0CR1<BC> to
"001" and write dummy data
(0x00)
2345678
1
9
D7
D5
D6
D4
D3
D2
D1
D0
Figure 18-20 Termination of Data Transfer in the Master Receiver Mode
18.5.3.2
When SBI0SR2<MST> is "0" (Slave mode)
In the slave mode, a serial bus interface circuit operates either in the normal slave mode or in the slave
mode after losing arbitration.
In the slave mode, the conditions of generating the serial bus interface interrupt request (INTSBI0) are
follows:
·
At the end of the acknowledge signal when the received slave address matches the value set by
the I2C0AR<SA> with SBI0CR1<NOACK> set at "0"
·
At the end of the acknowledge signal when a "GENERAL CALL" is received with
SBI0CR1<NOACK> set at "0"
·
At the end of transferring or receiving after matching of slave address or receiving of "GENERAL
CALL"
The serial bus interface circuit changes to the slave mode if arbitration is lost in the master mode. And an
interrupt request occurs when the word data transfer terminates after losing arbitration. The generation of the
interrupt request and the behavior of SBI0CR2<PIN> after losing arbitration are shown in
Table 18-4.Table 18-4 The Behavior of an interrupt request and SBI0CR2<PIN> After Losing Arbitration
When the Arbitration Lost Occurs during Transmission
of Slave Address as a Master
When the Arbitration Lost Occurs during Transmission
of Data as Master Transmitter
interrupt request
An interrupt request is generated at the termination of word-data transfer.
SBI0CR2<PIN>
SBI0CR2<PIN> is cleared to "0".
When an interrupt request occurs, SBI0CR2<PIN> is reset to "0", and the SCL0 pin is set to the low level.
Either writing data to the SBI0DBR or setting SBI0CR2<PIN> to "1" releases the SCL0 pin after taking
tLOW.
TMP89FH42
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