PNI SeaTRAX - Manual (Page 55)

PNI Sensor Corporation DOC#1018154 r02
SeaTRAX User Manual Page 50
would be in the filter. Once the taps are cleared, it is necessary to fully repopulate the
filter before data is output. For example, if 32 FIR taps is set, 32 new samples must be
taken before a reading will be output. The length of the delay before outputting data is
directly correlated to the number of FIR taps.
The payload for kSetFIRFilters is given below.
Byte 1 should be set to 3 and Byte 2 should be set to 1. The third payload byte indicates
the number of FIR taps to use, which can be 0 (no filtering), 4, 8, 16, or 32. This is
followed by the tap values, where 0 to 32 total Values can be in the payload, and with
each Value being a Float64, with suggested values given in Table 7-6.
Table 7-6: Recommended FIR Filter Tap Values
Count 4-Tap Filter 8-Tap Filter 16-Tap Filter 32-Tap Filter
1 04.6708657655334e-2 01.9875512449729e-2 07.9724971069144e-3 01.4823725958818e-3
2 04.5329134234467e-1 06.4500864832660e-2 01.2710056429342e-2 02.0737124095482e-3
3 04.5329134234467e-1 01.6637325898141e-1 02.5971390034516e-2 03.2757326624196e-3
4 04.6708657655334e-2 02.4925036373620e-1 04.6451949792704e-2 05.3097803863757e-3
5 02.4925036373620e-1 07.1024151197772e-2 08.3414139286254e-3
6 01.6637325898141e-1 09.5354386848804e-2 01.2456836057785e-2
7 06.4500864832660e-2 01.1484431942626e-1 01.7646051430536e-2
8 01.9875512449729e-2 01.2567124916369e-1 02.3794805168613e-2
9 01.2567124916369e-1 03.0686505921968e-2
10 01.1484431942626e-1 03.8014333463472e-2
11 09.5354386848804e-2 04.5402682509802e-2
12 07.1024151197772e-2 05.2436112653103e-2
13 04.6451949792704e-2 05.8693165018301e-2
14 02.5971390034516e-2 06.3781858267530e-2
15 01.2710056429342e-2 06.7373451424187e-2
16 07.9724971069144e-3 06.9231186101853e-2
17 06.9231186101853e-2
18 06.7373451424187e-2
19 06.3781858267530e-2
Byte 1
UInt8 UInt8
Payload
ID Specific ID Specific ID Specific ID Specific
Byte 2 Count N Value 2 Value 1 Value N Value 3
UInt8