DS1075

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TRANSACTION SEQUENCE

The sequence for accessing the DS1075 via the 1-Wire port is as follows:

Initialization

Function Command

Transaction/Data

INITIALIZATION

All transactions on the 1-Wire bus begin with an initialization sequence. The initialization sequence

consists of a reset pulse transmitted by the bus master followed by a presence pulse(s) transmitted by the

DS1075. The presence pulse lets the bus master know that the DS1075 is present and is ready to operate.

Figure 13

FUNCTION COMMANDS

Once the bus master has detected a presence, it can issue one of the four function commands. All

Function Commands are eight bits long, and are written lsb first. A list of these commands follows:

Write DIV Register [01H]

This command allows the bus master to write to the DS1075’s DIV register.

Read DIV Register [A1H]

This command allows the bus master to read the DS1075’s DIV register.

Write MUX Register [02H]

This command allows the bus master to write to the DS1075’s MUX register.

Read MUX Register [A2H]

This command allows the bus master to read the DS1075’s MUX register.

TRANSACTION/DATA

Immediately following the Function Command, the nine data bits are written to or read from the DS1075.

This data is written/read lsb first. The following diagrams illustrate the timing. Once data transfer is

complete a new transaction sequence can be started by re-initializing the device. Therefore to program

both the DIV and MUX registers two complete transaction sequences are required.