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

Figure 2.12 Two-Wire Serial Master Data Transmit and Receive
Set ES0 Bit In
Register 0xFD01
Read Status
Register (0xFD01)
Yes
BB_N = 0?
(0xFD01 Bit 0)
No
Write Device ID To
Data Register (0xFD00)
Set Start Bit In Control
Register (0xFD01)
Read Status
Register (0xFD01)
No
PIN Bit = 0?
(FC01 Bit 7)
Yes
A
Master Receive
2-20
One Byte Left?
Yes
Clear ACK Bit In
Control Register
First Byte?
No
Read Data From Data
Register (0xFD00)
Read Status
Register (0xFD01)
PIN Bit = 0?
(0xFD01 Bit 7)
Yes
No
Last Byte?
Yes
Write Stop Bit In Control
Register (0xFD01)
Read Last Byte From
Data Register (0xFD00)
End Read
Functional Description
A
Read
Read
or Write?
(LSB = 1 or
0?)
No
Yes
Read Dummy Byte
From Data Register
No
Write
Master Transmit
Write Data to Data
Register (0xFC00)
Read Status
Register (0xFD01)
No
PIN Bit = 0?
(0xFD01 Bit 7)
Yes
No
Last Byte?
Yes
Write Stop Bit In
Control Register
(0xFD01)
End Write
Note: All register locations given
are for 2-wire serial port 0.
Two-wire serial port 1
transfers operate in similar
fashion.