ADB Micro-Scope II, Instruction Manual

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Micro-Scope II
Lighting Technologies
MAX/MIN Mode
Max/Min mode is the "Flicker Finder". A single DMX512 channel is displayed as the
current value, minimum value and maximum value. All three numbers are decimal
0 to 255. This mode will capture any fluctuations in the lever of a channel.
To clear the Max and Min values, press the MENU key twice. When data is not received
on the selected channels, the Max value is set to 0, and the Min value to 255.
001 CUR 154
MIN 153 MAX 155
Detail Mode
Detail mode provides four further pieces of information about the DMX signal.
The Period "P" is the time between received Breaks on the DMX512 signal.
The reciprocal of this number gives the refresh rate.
The second number is the Break time "Bk". This is the length of the synchronising code
used to restart a new DMX frame. The specification requires this value to be 88uS or
greater. If this is not the case, the timing error icon "T" will be displayed in the main receive
window.
The third number "C" represents the number of dimmer channels received in the last
DMX packet. This number should be constant, although the value may be less than 512,
depending on the type of console used.
The fourth number is the Mark after Break time "MaB". This is the delay between the end
of a Break and transmission of the header code. The specification requires a MaB of 4us
or greater. If this is not the case, the timing error icon "T" will be displayed in the main
receive window. (The MaB limit was increased to 8uS in the DMX512 1990 Revision).
P = 023MS BK = 150US
C = 512 MAB = 012US
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
falling edge of the break or the DMX base address.
⇔
45.2uS
⇔
52.8uS
TRIGGER
DMX512
BREAK Start bit goes low DIMMER n
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