Zebra Technologies TTP 7030 - Manual (Page 90)

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Parameters Used 90
P1003636-002 TTP 7030™ Technical Manual 10/05/2009
Garbage, Black Mark and Out of Paper Detection
For every step the paper is feed, the black mark sensor is sampled to detect garbage, black
marks or out of paper.
When the printer detects blackness is has to check if it is only garbage;
The 5-mm is a constant added to make sure that noise on the edge not will interfere with the
samples. If it at this point still is still black we have detected out of paper.
Be careful about n40 and n39. If n39 – n40 is too small, then the minimum detection area will
be too little. This area should not be less than 2 mm.
Garbage range n40
Printed black mark n39
Valid black mark range (n39 – n40 + 5mm)
5 mm
Constant
Out of paper
If… Then…
the paper gets white again within n40 x
0.125 mm it is garbage and the spot is ignored.
it is still black after n40 x 0.125 mmYes it is probably a black mark.
the paper gets white within an additional
n39-n40 plus 5 mm it is a Blackmark