HD6432633 Datasheet, PDF (890/1453 Pages) Renesas Technology Corp – Series of Microcomputers (MCUs: microcomputer units)

[2] When ICDR is read (dummy data read), reception is started, and the receive clock is output,
and data received, in synchronization with the internal clock.
[3] The IRIC flag is set to 1 by the following two conditions. At that point, an interrupt request is
issued to the CPU if the IEIC bit in ICCR is set to 1.
1. The flag is set at the falling edge of the 8th clock cycle of the receive clock for 1 frame.
SCL is automatically held low, in synchronization with the internal clock, until the IRIC
flag is cleared.
2. The flag is set at the rising edge of the 9th clock cycle of the receive clock for 1 frame.
The IRIC flag and ICDRF flag are set to 1, indicating that reception of 1 frame of data has
ended. The master device continues to output the receive clock for the receive data.
[4] Read the IRTR flag in ICSR. If the IRTR flag value is 0, the wait state is cancelled by
clearing the IRIC flag as described in step [6] below. If the IRTR flag value is 1 and the next
receive data is the final receive data, perform the end processing described in step [7] below.
[5] If the IRTR flag value is 1, read the ICDR receive data.
[6] Clear the IRTR flag to 0. If condition [3]-1 is true, the master device drives SDA to low level
and returns an acknowledge signal when the receive clock outputs the 9th clock cycle.
Further data can be received by repeating steps [3] through [6].
[7] Set the ACKB bit in ICSR to 1 to set the acknowledge data for the final receive.
[8] Wait for at least 1 clock cycle after the IRIC flag is set to 1 and then wait for the rising edge
of the 1st clock cycle of the next receive data.
[9] Set the TSR bit in ICCR to 1 to switch from the receive mode to the transmit mode. The TSR
bit setting value at this point becomes valid when the rising edge of the next 9th clock cycle
is input.
[10] Read the ICDR receive data.
[11] Clear the IRTR flag to 0.
[12] The IRIC flag is set to 1 by the following two conditions.
1. The flag is set at the falling edge of the 8th clock cycle of the receive clock for 1 frame.
SCL is automatically held low, in synchronization with the internal clock, until the IRIC
flag is cleared.
2. The flag is set at the rising edge of the 9th clock cycle of the receive clock for 1 frame.
The IRIC flag and ICDRF flag are set to 1, indicating that reception of 1 frame of data has
ended. The master device continues to output the receive clock for the receive data.
[13] Read the IRTR flag in ICSR. If the IRTR flag value is 0, the wait state is cancelled by
clearing the IRIC flag as described in step [14] below. If the IRTR flag value is 1 and the
receive operation has finished, perform the issue stop condition processing described in step
[15] below.
[14] If the IRTR flag value is 0, clear the IRIC flag to 0 to cancel the wait state. Return to reading
the IRIC flag, as described in step [12], to detect the end of the receive operation.
[15] Clear the WAIT bit in ICMR to 0 to cancel the wait mode. Then clear the IRIC flag to 0. The
IRIC flag should be cleared when the value of WAIT is 0. (The stop condition may not be
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