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DMXtoDALI quad User Guide
Continuous Query (Switch 3)
Query Disable (Switch 4)
Activate (Switch 5)
When querying is enabled (i.e. the default mode corresponding to Switch 4 = Off, see below),
its mode of operation can be modified by this switch.
In its default mode of operation (Switch 3 = Off), DMXtoDALI will send two consecutive queries
at startup. The delay between each is approximately two minutes. This allows the DALI devices
time to boot. DMXtoDALI maps all the device responses and disables any further unicast to
devices that did not respond.
The default mode of operation means that DMXtoDALI would require a reboot to detect new DALI
devices or short address changes. While this is normally not a problem, it can be inconvenient
during installation.
DMXtoDALI can be set to query continuously every two minutes (Switch 3 = On). The query
process takes lower priority to level and colour data.
When DMXtoDALI is using a personality that unicasts directly to DALI devices, large amounts of
DALI bandwidth can be consumed by small changes on the DMX512 input. In order to manage
DALI bandwidth, DMXtoDALI will only unicast to a device that is actually connected.
DMXtoDALI achieves this by a process of querying all DALI devices.
In some instances, particularly in multi-master systems or if unicast is not being used, querying
may not be desired or needed and can be disabled (Switch 4 = On). Note that when querying
is disabled, DMXtoDALI will not be able to report back the number of DALI devices detected
using the RDM sensors.
In its default mode of operation (Switch 5 = Off), DMXtoDALI will send a DALI Activate command
after all DT8 colour data. This ensures that colour changes are immediately activated.
DALI devices can be configured to activate colour change in different ways - for example, linked
to the next level change. In this scenario the Activate command is not required (Switch 5 = On).
Buffering (Switch 2)
There is a vast difference between the speed at which DMX512 and DALI operate. This means
that when DMX512 levels change rapidly, not all the data can be converted to DALI. There are
two possible approaches to solving this problem.
In its default mode of operation (Switch 2 = Off), DMXtoDALI has a 16-deep buffer for each
DALI circuit. The buffer allows the differing speeds to be matched and smooths the conversion.
However, in some scenarios (with fast moving effects) a better visual result will be achieved by
dropping DMX512 frames. This is achieved by disabling buffering (Switch 2 = On).
