Rainbow Electronics DS2409 - Manual (Page 5)

DS2409
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STATUS CONTROL BYTE Table 1
7 6 5 4 3 2 1 0
DATA
X
CNTR.
SEL.
MODE R/ W R/ W X X X
0-2 X don’t care
3-4 R/ W
Write control: both bits must be 0 to change the status.
5 MODE control output mode selection: 0 = auto-control mode (default), 1 = manual mode
6
CNTR.
SEL.
control output association (auto-control mode): 0 = main (default), 1 = auxiliary
7
DATA
X
Value to be written to control output (manual mode only): don’t care otherwise
STATUS INFO BYTE Table 2
7 6 5 4 3 2 1 0
MODE
CNTR.
STAT
EVNT
AUX.
EVNT
MAIN AUX.
LEVL
AUX.
STAT
MAIN
LEVL
MAIN
STAT
0
MAIN
STAT
status of main output: 0 = active (connected to bus master), 1 = inactive
1
MAIN
LEVL
voltage sensed at main output: 0 = low, 1 = high (see note)
2
AUX.
STAT
status of auxiliary output: 0 = active (connected to bus master), 1 = inactive
3
AUX.
LEVL
voltage sensed at auxiliary output: 0 = low, 1 = high (see note)
4
EVNT
MAIN
event flag for main output: 0 = no event, 1 = negative edge sensed since inactive
5
EVNT
AUX.
event flag for aux. Output: 0 = no event, 1 = negative edge sensed since inactive
6
CNTR.
STAT
if auto-control mode: control output association, 0 = main, 1 = auxiliary
if manual mode: 0 = output transistor off, 1 = output transistor on
7 MODE control output mode: 0 = auto-control mode, 1 = manual mode
NOTE:
Data is valid only if the output is decoupled from the 1-Wire input.
ALL LINES OFF [66h]
This command is used to deactivate the currently active 1-Wire output and to clear both event flags or to
end a discharge cycle initiated by the Discharge Lines command. Before issuing this command, one
should read the status and check the event flags of both, the main and the auxiliary output. Otherwise one
might inadvertently clear the event flag without having taken appropriate action. If the DS2409 is in auto-
control mode, the transistor at the control output will be switched off (non-conducting). At power-on, the
device will automatically perform the All Lines Off command. In contrast to a power-on cycle, the All
Lines Off command does not clear the Mode and Control Select bits.