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Binary I/O Table

The Binary I/O table is where binary (off/on) inputs and outputs are read and written.The OID numbers below correspond to the start of each column in the table, and the row values for that column will be found "below" the listed OID number.

Binary I/O ID ( This is the sequence number for this row. It is typically not used for this table.

Binary I/O Description ( This is the description of this Binary I/O. It can be read and written. The description is limited to 16 characters. We recommend either leaving it as is, or setting it to a better description of what is connected to this I/O point.

Binary I/O Slot ( This is the Slot (Module) number for this Binary I/O. It corresponds to the Slot number in the Expansion Module table. 0 is the base unit, 1 is the first Expansion unit, and so on. It should be noted that the slot number will not necessarily correspond to the physical arrangement of expansion modules.

Binary I/O Position ( This is the Position Number of this Binary I/O. It will be the same for all identical modules. For instance, position 0 of the relay output module will always correspond to the first relay output. The relation between position and the exact I/O is documented in each expansion module's documentation.

Binary I/O Value ( read-write value contains the actual status of the Binary I/O. When reading this value, it will always be a 1 or a 0, where 1 is active and 0 is not active. For outputs, writing a 1 or a 0 to this value will set that output to a state corresponding to the value written. For inputs, writing to this value will have no effect.

Binary I/O PowerOn Value ( read-write value contains the status which the Binary Output is set to upon power on. For instance, if you write a value of '1' to this OID, upon power on, the corresponding output will be turned on. We recommend that this be left at 0 unless there is a good reason. Please see the documentation on outputs to determine when restoring an output to '1' at power on makes sense. For Inputs, this value always reads as a '0', and writes are ignored.

Binary I/O Cycle ( Writing a non-zero value to this OID will result in the corresponding binary output being toggled for a length of time corresponding to the value written. The value is nominally in tenths of seconds. As an example, if you have an output which starts out at the '0' state, and you write '30' to this OID, the site monitor will switch the output to '1' for 3 seconds, and then return the output to '0' after the timer has elapsed. Reading this value will show either 0 if the cycle timer is not active, or the remaining time if it is. For inputs, this value always reads as a '0', and writes are ignored.

Binary I/O Events ( This read/write value counts the number of toggles of the binary Input or Output. That is, this OID increments each time the binary Input or Output switches from 1 to 0 and from 0 to 1. This value is rate-limited (debounced) on most modules to help prevent one event from incrementing the counter multiple times due to switch bounce or other similar "noise" sources. This OID can be written with any value, but the most common use is to write a '0' to reset the counter.

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