DS2409(3)

NAME
DS2409 - MicroLAN Coupler

SYNOPSIS
1-wire network branch controller.

1F [.]XXXXXXXXXXXX[XX][/[ aux | branch.[0|1|ALL|BYTE] | control | discharge | event.[0|1|ALL|BYTE] | clearevent | main | sensed.[0|1|ALL|BYTE] | ]]

FAMILY CODE

1F

SPECIAL PROPERTIES

  aux
directory
This is the aux branch of the DS2409 network branch. It is implicitly accessed (via the aux smart-on command) when it is listed or devices on this branch are addressed.

  branch.0 branch.1 branch.ALL branch.BYTE
read-only, yes-no
Is the branch ( 0=main or 1=aux ) currently connected to the master bus? Value returned is 1 (yes) or 0 (no). The DS2409 should not allow both to be on simultaneously.
ALL is an aggregate of the properties, comma separated. It is an atomic operation.
BYTE is an aggregate of the branches as a byte, A is bit 0.

  control
read-write, unsigned integer
Setting of the PIO control pin. There are 4 possible settings:

0   Unconditionally off (non-conducting)

1   Unconditionally on (conducting)

2   Auto on when main branch switched in

3   Auto on when aux branch switched in

  discharge
write-only, yes-no
Writing a non-zero value to this property will electrically reset both the main and auxillary branches of the 1-wire bus by dropping power for 100 milliseconds. All devices on those branches will lose parasitic power and reset to power-up defaults. As a side effect, both event flags and thus, the alarm state, are cleared, too.

  event.0 event.1 event.ALL event.BYTE
read-only, yes-no
Has the event flag for the branch been triggered? A negative edge on the disconnected branch ( 0=main or 1=aux ) sets the flag. This is achieved by e.g. connecting an iButton to the branch. Value returned is 1 (yes) or 0 (no). ALL is an aggregate of the properties, comma separated. It is an atomic operation.
BYTE is an aggregate of the branches as a byte, main is bit 0.

  clearevent
write-only, yes-no
Writing a non-zero value to this property will reset both event flags and thus, clear the alarm state, too.

  main
directory
This is the main branch of the DS2409 network branch. It is implicitly accessed (via the main smart-on command) when it is listed or devices on this branch are addressed.

  sensed.0 sensed.1 sensed.ALL sensed.BYTE
read-only, yes-no
Voltage sensed at the 0=main or 1=aux branch pin. Valid only when the branch is switched out. Value returned is 0 (low) or 1 (high).
ALL is an aggregate of the properties, comma separated. It is an atomic operation.
BYTE is an aggregate of the branches as a byte, A is bit 0.

STANDARD PROPERTIES

ALARMS
The DS2409 will respond to a conditional search if the main event flag is set.

DESCRIPTION

  DS2409
The DS2409 (3) allows complex 1-wire network topology. Each branch has it's power preserved, even when isolated from the master. A separate PIO pin can be configured to show branch switching, or controlled explicitly.

ADDRESSING

DATASHEET
http://pdfserv.maxim-ic.com/en/ds/DS2409.pdf

SEE ALSO

AVAILABILITY
http://www.owfs.org

AUTHOR
Paul Alfille (palfille@earthlink.net)