LSI53C040-160QFP LSI, LSI53C040-160QFP Datasheet - Page 33

• Manufacturer Part Number: LSI53C040-160QFP
• Manufacturer: LSI

Specifications of LSI53C040-160QFP

• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Supplier Unconfirmed

2.6 Two-Wire Serial Interface Operation
Figure 2.8
Master
Slave
Figure 2.9
Master
Slave
Control Byte
Control Byte
Device ID
Device ID 0
Serial Read Operation
Serial Write Operation
R/W
R/W
Bit
ACK
Bit
ACK
0
To enter ONCE mode, hold ALE low while bringing RESET/ to low, then
releasing it to high. ONCE mode should be used for testing or diagnostic
purposes only, and should be disabled during normal chip operation.
The Two-Wire Serial interface performs two main functions: it
automatically downloads firmware from an external serial EEPROM
device, and it serves as a Two-Wire Serial port with full multimaster and
slave capability that can communicate with external Two-Wire Serial
devices. The Two-Wire Serial interface in the LSI53C040 provides the
microcontroller an additional means to gather external system
information. The Two-Wire Serial interface supported by the LSI53C040
is compliant with the Inter-Integrated Circuit bus defined by Philips
Electronics.
operation.
operation.
Two-Wire Serial Interface Operation
(1 or 2 Bytes)
Address Byte
Address Byte
Figure 2.9
Figure 2.8
ACK
ACK
Data Byte
Control Byte
illustrates serial bus activity during a write
Device ID
illustrates serial bus activity during a read
ACK
1
ACK
Data Byte
by an ACK, up
each followed
bytes may be
to capacity of
slave device)
ACK
transferred,
(More data
(More data bytes
each followed by
transferred,
an ACK)
may be
Last Data Byte
Last Data Byte
ACK
ACK
No
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