File format:Tektronix WFM

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Revision as of 11:18, 30 December 2014 by Uwe Hermann (talk | contribs) (Uwe Hermann moved page File format:Tek WFM to File format:Tektronix WFM without leaving a redirect)
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The Tek WFM format is a special format used by TDS Series scopes. It uses less space than the CSV/Matlab export functions provided.

Header

Bytes Field
0 - 1 Magic Bytes
2 - 5 Format Code
6 Length of Data, Unsigned integer (so far always 4)
7 - 11 Number of bytes following
12 - 15 Another Magic
16-20 Length of Header + Data (big endian, signed integer)
21 - 28 Vertical Position (Double)
29 - 36 Horizontal Position (Double)
37 - 43 Vertical Zoom (Double)
44 - 51 Horizontal Zoom (Double)
52 - 53 Acquisition Mode (signed integer, currently unknown)
54 - 55 Min Max (unknown)
56 - 63 Duration in seconds (double)
63 - 64 Vertical Coupling (signed integer)
65 - 66 Horizontal Unit (signed integer)
67 - 74 Horizontal time per point (double)
75 - 76 Vertical Unit (signed integer)
77 - 84 Vertical Offset (double)
85 - 92 Vertical Position (double)
93 - 100 Vertical Gain (double)
101 - 105 Record length (unsigned integer)
106 - 107 Trigger Position (signed integer), possibly in points
108 - 109 Header Version (signed integer)
110 - 111 Sampling Density (??) (signed integer)
112 - 113 Burst Segment Length (signed integer)
114 - 115 Waveform Source (signed integer)
116 - 121 3x Video 1 (signed integer)
122 - 129 Video 2 (double)
130 - 131 Video 3 (signed integer)
131 - 163 Preamble (???)

Data

Waveform data. Length of this segment is stored in Record length.

To reconstruct the waveform use the following:

y = data[i] * vertgain / 25 / 256 + vertoffset - vertposition * vertgain
x = (i - (reclength*trigpos/100)) * horizscaleperpoint