Artistic Licence DMX-Dongle II, Руководство пользователя

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Artistic Licence (UK) Ltd. DMX-Dongle User’s Guide 15
Status
Window
The Status window provides the following information:
Chan
The number of channels received in the last DMX frame. This
number may vary from 1 - 512 depending on the transmitting
console. It should however remain stable at a particular value
Period
The repeat time of the last two consecutive DMX frames. This
value shows how fast the console is transmitting information. As
the value increases beyond 50mS you will start to notice lamp
fades become 'lumpy'. The actual value will depend on the
console but should be about 25-30mS.
Refresh
The refresh rate is the reciprocal of the period. It is measured
in Hz and therefore shows the number of DMX frames received
per second. It should be in the range 30Hz to 40Hz.
Break
The length of the break signal. The break signal is used to
synchronise frames of DMX data. The specification requires
this value to be greater than 88uS. The actual value is console
dependent but usually in the range 100uS to 300uS. A value of
less than 88uS shows that a problem exists with the
transmitting console.
MaB
The Mark after Break length. The MaB is the time delay
between the end of the break signal and transmission of the
header code. The specification requires this value to be greater
than 8uS. The actual value is console dependant but usually
about 20uS. Prior to the 1990 upgrade to the DMX512
specification a MaB time of 4uS was allowed. This was changed
because it put an unnecessarily onerous demand on the receive
electronics. Modern receivers may not receive DMX with a MaB
time of less than 8uS.
Start
The Header code is in theory used to identify the type of data
contained in the DMX512 frame. In practice almost all
manufacturers use a zero header code irrelevant of the
intended destination of the DMX signal.
The Header code can be programmed with the F3 key. DMX-
Analysis will only display data with a matching header code.
If your DMX signal contains data with different header codes,
you can investigate the data using this field and also the Bad
Header count in the Error Log.