System information

Artistic Licence Engineering Ltd. Micro-Scope 3a Manual
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TRIGGER
OUTPUT
The spare two pins of the DMX512 output are used to provide a
TTL (5V) oscilloscope trigger output. This signal can be used to
synchronise the oscilloscope to either the start code or the DMX
base address.
The operation of the scope trigger has been greatly improved from
firmware V7.1 onwards. In previous versions the scope trigger
output a pulse synchronised to Break and selected display start
address.
In this release the scope trigger is now synchronised to the start
code selected in menu 4. The rising edge of the scope trigger
occurs 50uS after detection of a DMX512 packet with the selected
start code. This allows a scope to be used to view DMX512 frames
with a specific start code.
The falling edge remains synchronised to the start address
selected in menu 1. This is useful for two reasons:
1) It allows a specific data slot to be viewed on a scope by
triggering on the falling edge of the scope trigger.
2) If the start address is set to a large value, the trigger will
only occur for packets containing at least that many slots.
DMX512 packets such as RDM are variable length, so it is
possible to capture specific length packets on the scope.
DMX512
52uS
55uS
TRIGGER
R
Start Code
Start bit goes low
DIMMER n
End of Break