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17.4.4
Slave Transmit Operation
In slave transmit mode, the slave device outputs the transmit data, while the master device outputs
the receive clock and returns an acknowledge signal. The operation timings in slave transmit mode
are shown in figures 17.9 and 17.10.
The transmission procedure and operations in slave transmit mode are described below.
1. Set the ICE bit in ICCRA to 1. Set the WAIT bit in ICMR and the CKS3 to CKS0 bits in
ICCRA to 1 (initial setting). Set the MST and TRS bits in ICCRA to select slave receive mode,
and wait until the slave address matches.
2. When the slave address matches in the first frame following detection of the start condition,
the slave device outputs the level specified by ACKBT in ICIER to SDA, at the rise of the 9th
clock pulse. At this time, if the 8th bit data (R/W) is 1, the TRS in ICCRA and TDRE in ICSR
are set to 1, and the mode changes to slave transmit mode automatically. The continuous
transmission can be performed by writing transmit data to ICDRT every time TDRE is set.
3. If TDRE is set after writing the last transmit data to ICDRT, wait until TEND in ICSR is set to
1, with TDRE = 1. When TEND is set, clear TEND.
4. Clear TRS for the end processing, and read ICDRR (dummy read). Then, SCL is free.
5. Clear TDRE.
Rev. 1.00, 09/03, page 496 of 704
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