Single-Channel 1-Wire Master

10

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Write Configuration

Command Code

D2h

Command Parameter

Configuration Byte

Description

Writes a new configuration byte. The new settings take effect immediately. Note: When writing to

the Configuration Register, the new data is accepted only if the upper nibble (bits 7 to 4) is the

one’s complement of the lower nibble (bits 3 to 0). When read, the upper nibble is always 0h.

Typical Use

Defining the features for subsequent 1-Wire communication.

Restriction

1-Wire activity must have ended before the DS2482-100 can process this command.

Error Response

Command code and parameter are not acknowledged if 1WB = 1 at the time the command code

is received and the command is ignored.

Command Duration

None. The Configuration Register is updated on the rising SCL edge of the configuration-byte

acknowledge bit.

1-Wire Activity

None

Read Pointer Position

Configuration Register (to verify write).

Status Bits Affected

RST set to 0.

Configuration Bits Affected

1WS, SPU, APU updated.

1-Wire Reset

Command Code

B4h

Command Parameter

None

Description

Generates a 1-Wire reset/presence-detect cycle (Figure 4) at the 1-Wire line. The state of the

Status Register, bits PPD and SD.

Typical Use

To initiate or end any 1-Wire communication sequence.

Restriction

1-Wire activity must have ended before the DS2482-100 can process this command.

Error Response

Command code is not acknowledged if 1WB = 1 at the time the command code is received and

the command is ignored.

Command Duration

acknowledge bit.

1-Wire Activity

Begins maximum 262.5ns after the falling SCL edge of the command code acknowledge bit.

Read Pointer Position

Status Register (for busy polling).

Status Bits Affected

Configuration Bits Affected

1WS and APU apply.