PD72042B_15 Datasheet, PDF (53/92 Pages) Renesas Technology Corp – LSI DEVICE FOR Inter Equipment BusTM (IEBusTM) PROTOCOL CONTROL

µPD72042B
(b) Slave reception
Slave reception is performed when the broadcast bit is set to 1, and a communication frame with the local
station address specified in the slave address field is received.
Table 4-7 indicates the SLRC return codes for slave reception.
Table 4-7 SLRC Return Codes for Slave Reception
SLRC
0100
Description
1. Meaning: Slave reception is started.
2. Occurrence condition:
1 A separate communication frame up to the data-length field was received normally from the
master unit.
2 Once the control field has been received, RBF is ready for reception^Note.
0101
0110
0111
After the data-length field, 0100 is set in SLRC, and three-byte data consisting of a master address,
control bits, and data-length bits is set in RBF.
3. Microcomputer processing: Three-byte data consisting of a master address, control bits, and data-
length bits can be read from RBF.
1. Meaning: The slave reception buffer is full.
2. Occurrence condition: This return code is issued when RBF becomes full during data reception as a
slave unit, and reception data cannot be set in RBF.
3. Microcomputer processing: If data consisting of one or more bytes is not read from RBF within the
period indicated below, the one-byte data cannot be received, and the µPD72042B returns an NAK.
• Reception data read time: Approx. 1570 µs (mode 0)
Approx. 390 µs (mode 1)
1. Meaning: Slave reception was terminated normally.
2. Occurrence condition: This return code is issued when as much data as the amount specified in the
data-length field has been received normally in a communication frame. In this case, the SLRE flag of
the FLG register changes from 1 to 0.
3. Microcomputer processing: Reception data can be read from RBF, and the number of bytes of slave
reception data can be read from RDR2.
1. Meaning: Slave reception was aborted.
2. Occurrence condition: This return code is issued when reception is terminated prior to the reception
of as much data as the amount specified in the data-length field of a communication frame. In this
case, the SLRE flag of the FLG register changes from 1 to 0.
3. Microcomputer processing: Reception data can be read from RBF, and the number of bytes of slave
reception data can be read from RDR2.
Note See Note of Table 4-9.
Data Sheet S13990EJ3V0DS
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