Two-Wire Serial Slave Data Transmit And Receive - LSI Symbios SYM53C040 Technical Manual

Figure 2.11 Two-Wire Serial Slave Data Transmit and Receive
R/W = 1
Slave Transmit
Read Byte From
Control/Status
Register
No
PIN Bit = 0?
Yes
No
Yes
ACK Received?
(LRB = 1?)
No
Write Data to Data
Register
Write Dummy Byte
(0xFF) to Data
Register
End Transmit
Two-Wire Serial Interface Operation
Read Byte from
Control/Status
Register
No
PIN Bit = 0
?
Yes
Read Device
Address From Data
Register
AAS
No
Bit Set?
(0xFC03 Bit 2)
Yes
Read
R/W = 0
or Write?
(LSB = 1 or 0)
Read Byte From
Control/Status
PIN Bit = 0?
Detected?
(STS = 1?)
Read Data From
Data Register
Read Last Data
Byte From Data
PIN deactivated
(set to 1),
SYM53C040
goes into slave
End Receive
receiver mode
Interrupt Service
Routine
Slave Receive
Register
No
Yes
Stop
Yes
No
Register
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