Fujitsu F2MC-16LX MB90580 Series Hardware Manual page 203

(6) Master receive routine
After the master transmit the control bits, this routine is used for the master to receive data, slave address
or log address from the slave. This routine is consisted of four parts depending on the content of ST3-0.
1. Start of master reception (ST3-0 is 4H)
When the master receive the telegraph length field from the slave correctly, the status code 4H is set
and the master reception starts. However, interrupt will not occur at that time..
Note1
Note2
N
Note1: The status register need not be read because each registers are set. However, it is
required to take care the timing of setting the registers. Before updating the register
contents, read the registers first.
Note2: N is the number of data byte for master receive.
2. Master received data read request (ST3-0 is 5H)
Note1
Note1: Do not read RDB when RDBE=1.
Note2: N is the number of data byte for master receive.
MB90580 Series
Begin
Read multiaddress, control
bits and telegraph length bits
number of master receive data byte
End
Begin
I = 8
I I - 1
RDBE = 1?
N
RDB read
Note2
N N - 1
Read out multiaddress, control bits and
master receive byte number
Done by hardware
Master receive buffer size
Done by hardware
Done by hardware
Y
End
Done by hardware
13.5 Operation
Chapter 13: IE Bus 183