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Step 6 - Final Assembly

Assemble Encoder Disk and Board

The encoder disk is flexible and it should be possible to slip it into the sensors without too much trouble.

This photo shows a completed prototype, with the outputs hooked to a Basic Stamp. A simple thumbtack has been placed into the middle of the encoder disk, to act as a point of rotation.


Testing

The single-track Gray code sequence omits numbers 0 and 127 in the 7-bit sequence, meaning the sequence has 126 numbers instead of 128.

The following is the (decimal) sequence of numbers in the Gray code:

1, 5, 13, 9, 73, 89, 121, 125, 61, 53, 55,
39, 37, 101, 69, 71, 7, 3, 2, 10, 26, 18,
19, 51, 115, 123, 122, 106, 110, 78, 74,
75, 11, 15, 14, 6, 4, 20, 52, 36, 38, 102,
103, 119, 117, 85, 93, 29, 21, 23, 22, 30,
28, 12, 8, 40, 104, 72, 76, 77, 79, 111, 107,
43, 59, 58, 42, 46, 44, 60, 56, 24, 16, 80, 81,
17, 25, 27, 31, 95, 87, 86, 118, 116, 84, 92, 88,
120, 112, 48, 32, 33, 35, 34, 50, 54, 62, 63, 47,
45, 109, 105, 41, 57, 49, 113, 97, 96, 64, 66, 70,
68, 100, 108, 124, 126, 94, 90, 91, 83, 82, 114,
98, 99, 67, 65

This BasicStamp program demonstrates an example of decoding the single-track disk.

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