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OWLL(9) Kernel Developer's Manual OWLL(9)

NAME

owll OWLL_WRITE_ONE, OWLL_WRITE_ZERO, OWLL_READ_DATA, OWLL_REASET_AND_PRESENCE —
Dallas Semiconductor 1-Wire Link Layer Interface

SYNOPSIS

int
OWLL_WRITE_ONE(device_t lldev, struct ow_timing *timing);

int
OWLL_WRITE_ZERO(device_t lldev, struct ow_timing *timing);

int
OWLL_READ_DATA(device_t lldev, struct ow_timing *timing, int *bit);

int
OWLL_RESET_AND_PRESENCE(device_t lldev, struct ow_timing *timing, int *bit);

DESCRIPTION

The owll interface provides access to the link layer of the Dallas Semiconductor 1-Wire from upper layers of the protocol.

OWLL_WRITE_ONE() and OWLL_WRITE_ZERO() writes a one bit or a zero bit respectively on the 1-Wire bus.

OWLL_READ_DATA() reads one bit from the 1-Wire bus. This is often referred to as a “Read Time Slot” in the 1-Wire device data sheets.

The OWLL_RESET_AND_PRESENCE() function starts a reset sequence and detects if any device(s) are present on the bus. This is the beginning of all 1-Wire transactions.

NOTES

This interface is intended to be used only by the ow(4) device to talk to the low-level bus. By convention, the device that implements this interface is called owc(4). Only devices that implement own(9) should call these interfaces.

SEE ALSO

ow(4), owc(4), own(9)

LEGAL

1-Wire is a registered trademark of Maxim Integrated Products, Inc.

HISTORY

The owll driver first appeared in FreeBSD 11.0.

AUTHORS

The owll device driver and this manual page were written by Warner Losh.
September 22, 2016 Linux 4.19.0-10-amd64