![](http://datasheet.mmic.net.cn/370000/UPD72042_datasheet_16740748/UPD72042_51.png)
μ
PD72042
51
Data Sheet S14870EJ1V0DS00
(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
Description
0100
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
.
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.
0101
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
μ
PD72042 returns an NAK.
Reception data read time:
Approx. 1570
μ
s (mode 0)
Approx. 390
μ
s (mode 1)
0110
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.
0111
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.