owll
,
OWLL_WRITE_ONE
,
OWLL_WRITE_ZERO
,
OWLL_READ_DATA
,
OWLL_REASET_AND_PRESENCE
—
Dallas Semiconductor 1-Wire Link Layer Interface
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);
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.
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.
1-Wire is a registered trademark of Maxim Integrated Products,
Inc.
The owll
driver first appeared in
FreeBSD 11.0.
The owll
device driver and this manual
page were written by Warner Losh.