AL250 International Power Sources, Inc., AL250 Datasheet - Page 17

• Manufacturer Part Number: AL250
• Description: Video Scan Doubler
• Manufacturer: International Power Sources, Inc.

The read/write command format is as follows:
Write: <S> <Write SA> <A> <Register Index> <A> <Data> <A> <P>
Read: <S> <Write SA> <A> <Register Index> <A> <S> <Read SA> <A> <Data> <NA> <P>
Following are the details:
<DATA>:
Data byte write to or read from the register index.
In read operation, the host must release the SDA line (high) before the first clock pulse is
transmitted to the AL250.
<S>:
Start signal
SCL
High
High
The Start signal is HIGH to LOW transition on
the SDA line when SCL is HIGH.
<WRITE SA>:
Write Slave Address: 58h or 5Ch
<READ SA>:
Read Slave Address: 59h or 5Dh
<REGISTER INDEX>:
Value of the AL250/251 register index.
<A>:
Acknowledge stage
The acknowledge-related clock pulse is generated
by the host (master). The host releases the SDA
line (HIGH) for the AL250/251 (slave) to pull
down the SDA line during the acknowledge clock
pulse.
<NA>:
Not Acknowledge stage
The acknowledge-related clock pulse is generated
by the host (master). The host releases the SDA
line (HIGH) during the acknowledge clock pulse,
but the AL250/251 does not pull it down during
this stage.
SDA
High
Low
SDA
SDA
SDA
SDA
SCL
SCL
SCL
SCL
SCL
AL250-15 I2C drawing
July 28, 1999
Data bit [1] or NA
Data bit [0] or A
Not significant
START bit [S]
STOP bit [P]
AL250
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