Initial work to understand Nike+iPod transmission data

Joined: 20 Jan 2008

nanousr wrote:

There is a typo in your data in the 8th line:

Code:

Data: AE 45 C9 CD FA 28 85 99 0D 6E 24 01 *010* 8D C9 AB 13 D7 BD 79 1A 32 76

Did you mean 01, or 10?

The checksum indicates it should be 10

Joined: 17 Feb 2008

A lot of information about this device online is misleading. When I first heard about this, the site I was reading claimed the transmitter didn't have a battery, and used the energy from the foot impact to power the burst transmission of the device's ID. This is what got me excited about the device in the first place: that it was so simple.

Other places I've read say there is an accelerometer inside. While not entirely inaccurate, it is again slightly misleading. It does not have an accelerometer the same way a Wii controller does. It has a piezoelectric sensor. (See SparkFun's Nike+iPod Dissection page)

I am not entirely confident that I know the capabilities of piezoelectric sensors, but if I am understanding correctly, they are primarily used to detect impact, and not smaller accelerations like the Wii controller does. What I am saying is that the sensor doesn't know it is being dropped, it just knows that it hits the table.

For this dump, I tapped the sensor on the table two times every second. It's two short taps followed by me waiting for the receiver to show it received a packet.

Code:

AF AC CD 2A 92 4E 71 EC 5B 3C 3A C9 72 EF 3A F0 75 AE 79 35 3E D9 B6
A0 B3 69 55 76 0F 7E 19 C4 95 A0 A5 21 33 B1 8F AC 1F F9 01 8E E6 BA
A1 23 53 40 75 8F 5C 2E 07 39 4B A3 97 12 26 BB EA 86 A4 3B 78 6E 80
A2 6F 27 1A B8 E4 5D 4F 80 05 19 6A A1 75 6C 0B 96 D5 59 69 B7 C7 78
A3 4A 58 38 55 F6 3D 1E B3 90 44 64 5B 5D 4F 9B 89 51 B8 CC 6E 3A 9C
A4 37 16 36 AC A0 B3 B5 08 86 94 4E D4 9E 1C 6E 5B 85 85 53 8D AB 1B
A5 FD AE FA 74 3B B6 88 CF 1B 95 32 56 75 BB F1 96 2B 19 A3 1D 73 E6
A6 45 59 1F 41 38 6A 20 60 FD AC 44 91 1F F4 E8 EE 1A 8B 43 CC A6 CB
A7 1C 94 06 CA E0 C4 7C 3F 87 4D 95 E8 9A 04 27 6D 4E 86 96 FC 11 D2
A8 57 53 73 E9 4B 58 92 CB FE 99 F5 C0 91 C1 90 1E C7 8C 04 A6 E9 72
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AB EF DC BC 6D 0B 8F 0A 30 22 9A 70 22 3E C8 CE 04 F5 2B 39 5F CE 33
AC 78 B4 0B F9 02 49 7C 05 4F 05 3B 2A 4D 4C F4 20 CD 73 16 2E 0F B1
AD 2B 17 0E 5A 70 77 26 3C F6 C8 1F 92 58 F7 72 00 0E 27 14 74 A2 23
AE A1 3E 49 FC EA 78 F6 A8 DA F9 AD AC 92 D4 E1 DF 35 A7 24 0D 6F B2
AF AC CD 2A 12 D2 ED 70 C8 AF A9 56 EF 72 9F 55 D0 49 56 1E 97 6E 62
A0 B3 69 55 F6 93 E2 85 61 30 05 48 CE DC 56 68 4B 46 40 48 85 1F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 36 2B 1F 03 6D 71 F4 08 2C 19 A8 26 9E 29 47 66 4A 91 8D
AB EF DC BC 6D 0B 8F 0A 30 22 9A 70 22 3E C8 CE 04 F5 2B 39 5F CE 33
AC 78 B4 0B F9 02 49 7C 05 4F 05 3B 2A 4D 4C F4 20 CD 73 16 2E 0F B1
AD 2B 17 0E 5A 70 77 26 3C F6 C8 1F 92 58 F7 72 00 0E 27 14 74 A2 23
AE A1 3E 49 FC EA 78 F6 A8 DA F9 AD AC 92 D4 E1 DF 35 A7 24 0D 6F B2
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92

This dump is from tapping it once per second on the table:

Code:

A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 7C D0 C3 C5 B8 36 24 BE 24 6E CC BE 8B B5 95 43 9D BB FB
A5 FD AE FA 44 4B C6 F8 FF 2B A5 42 26 05 CB 81 E6 9B 89 33 8D 03 66
A6 45 59 1F 11 68 3A 70 90 0D 5C F4 21 AF 44 58 5E 6A DB 13 9C 76 AB
A7 1C 94 06 9A 10 34 8C 0F B7 7D 65 18 6A F4 D7 9D FE 16 06 6C A1 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB

Something really interesting happens if you group all of the lines together that begin with AA, AB, etc. A lot of them match up! This is a re-arrangement of both dumps of data. Blue is from the "1 tap" set, red is from the "2 taps" set.

A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A0 B3 69 55 76 0F 7E 19 C4 95 A0 A5 21 33 B1 8F AC 1F F9 01 8E E6 BA
A0 B3 69 55 F6 93 E2 85 61 30 05 48 CE DC 56 68 4B 46 40 48 85 1F 4E
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E

A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A1 23 53 40 75 8F 5C 2E 07 39 4B A3 97 12 26 BB EA 86 A4 3B 78 6E 80
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE

A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A2 6F 27 1A B8 E4 5D 4F 80 05 19 6A A1 75 6C 0B 96 D5 59 69 B7 C7 78
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0

A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A3 4A 58 38 55 F6 3D 1E B3 90 44 64 5B 5D 4F 9B 89 51 B8 CC 6E 3A 9C
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E

A4 37 16 36 7C D0 C3 C5 B8 36 24 BE 24 6E CC BE 8B B5 95 43 9D BB FB
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A4 37 16 36 AC A0 B3 B5 08 86 94 4E D4 9E 1C 6E 5B 85 85 53 8D AB 1B
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB

A5 FD AE FA 44 4B C6 F8 FF 2B A5 42 26 05 CB 81 E6 9B 89 33 8D 03 66
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A5 FD AE FA 74 3B B6 88 CF 1B 95 32 56 75 BB F1 96 2B 19 A3 1D 73 E6
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66

A6 45 59 1F 11 68 3A 70 90 0D 5C F4 21 AF 44 58 5E 6A DB 13 9C 76 AB
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A6 45 59 1F 41 38 6A 20 60 FD AC 44 91 1F F4 E8 EE 1A 8B 43 CC A6 CB
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB

A7 1C 94 06 9A 10 34 8C 0F B7 7D 65 18 6A F4 D7 9D FE 16 06 6C A1 D2
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A7 1C 94 06 CA E0 C4 7C 3F 87 4D 95 E8 9A 04 27 6D 4E 86 96 FC 11 D2
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2

A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A8 57 53 73 E9 4B 58 92 CB FE 99 F5 C0 91 C1 90 1E C7 8C 04 A6 E9 72
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92

A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0

AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AA 06 85 D1 36 2B 1F 03 6D 71 F4 08 2C 19 A8 26 9E 29 47 66 4A 91 8D

AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AB EF DC BC 6D 0B 8F 0A 30 22 9A 70 22 3E C8 CE 04 F5 2B 39 5F CE 33
AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AB EF DC BC 6D 0B 8F 0A 30 22 9A 70 22 3E C8 CE 04 F5 2B 39 5F CE 33

AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AC 78 B4 0B F9 02 49 7C 05 4F 05 3B 2A 4D 4C F4 20 CD 73 16 2E 0F B1
AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AC 78 B4 0B F9 02 49 7C 05 4F 05 3B 2A 4D 4C F4 20 CD 73 16 2E 0F B1

AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AD 2B 17 0E 5A 70 77 26 3C F6 C8 1F 92 58 F7 72 00 0E 27 14 74 A2 23
AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AD 2B 17 0E 5A 70 77 26 3C F6 C8 1F 92 58 F7 72 00 0E 27 14 74 A2 23

AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AE A1 3E 49 FC EA 78 F6 A8 DA F9 AD AC 92 D4 E1 DF 35 A7 24 0D 6F B2
AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AE A1 3E 49 FC EA 78 F6 A8 DA F9 AD AC 92 D4 E1 DF 35 A7 24 0D 6F B2

AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
AF AC CD 2A 92 4E 71 EC 5B 3C 3A C9 72 EF 3A F0 75 AE 79 35 3E D9 B6
AF AC CD 2A 12 D2 ED 70 C8 AF A9 56 EF 72 9F 55 D0 49 56 1E 97 6E 62
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62

What's really strange to me is that I got a lot of the same lines, even just from tapping it not terribly accurately by hand. With that many bits, it is no coincidence that so many of them match up. This suggests to me that the resolution of data transmitted is not as great as I originally thought.

(This post is also on my blog)

Joined: 14 Apr 2007

OK,
here is a summary what we have so far:

- the sensor sends a byte sequence (see previous post) of data every second
- each byte sequence starts with a few bytes indicating Nike+ mode, the ID, etc.
- the pace/distance data etc must be in the remaining payload
- this paylod starts with an increment, and has a checksum at the end
- after 9 seconds of inactivity, there is no more transmission
- each byte sequence appears to look very different: even if the sensor rests, different sequences are sent
- however, these sequences seem to reappear, but independantly: getting some data, coming back the next day, doing another experiment, some of the data is identical with the day before (see previous post)
- there is no data stored in the sensor pod, e.g. if running with the sensor, and it comes out of wireless reach, the data does not accumulate once back in reach
- either the sensor pod or the ipod must do some analysis: if reading the data directly via USB without the iPod, a lot of different data is transmitted if the pod sensor is just tapped with the finger; however, if used with the ipod, it recognizes that these are not "real" steps, and does not count them towards the km/miles.
-the payload could be encrypted/compressed
- the wireless is rather flaky: a lot of byte sequences get lost even if transmitter/receiver are in close proximity=> there must be some redundancy built-in
- the sensor pod measures distance by measuring the time between the foot hitting the ground and releasing (according to apple site) => one would think it transmits two timestamps for that, however, that is a lot of data to put into the byte sequences (see examples)

That's all I could think of, let me know if you find anything else.
Thanks!

Contributor Joined: 11 Apr 2006 Location: Ontario, Canada

I can't really contribute to this discussion but I would like to point out that using your finger to rhythmically tap the sensor seems a bit odd to me. Not sure how you are running your trials but if you aren't doing so already, try placing the sensor flat on the table and making a motor-run device (e.g. you can make something simple out of Lego, etc.) that will tap it at exact intervals, then collect data for a few minutes. That could help clarify how timestamps are integrated into the data. If you are already using mechanical means for doing the tapping, please excuse my post Embarassed

On a side note, I don't think a device like this would be using an accelerometer for detecting the tapping. Correct me if I'm wrong, but I can't see how knowing your foot's instantaneous movements/acceleration would be useful to you (unless the user wants to maintain perfect running form or whatnot). But thats just my guess.

Joined: 10 Feb 2008

fmfmfm wrote:

There was an error in line 8, you are right. I have no idea how it got in there.

I captured some more data to illustrate:
Data: AF 06 91 88 16 E8 00 4A A1 86 B3 C2 4E 3C 85 AC 31 FD A3 40 AC 2F 03
Data: A3 2B BF 20 8F EB 1C 6E 6E A8 96 51 72 FC E6 BF 6B E1 17 9B C9 BA 1A
Data: A5 AC D4 E4 07 5E 09 3C 23 43 DE F6 DB E5 A5 84 D5 6E 08 7C 55 12 58
Data: A7 EF F2 C3 36 E5 54 77 0B 92 94 7A 82 9E 61 EC 26 BA 2B 4E C3 06 F1
Data: A8 23 26 51 50 7C 65 E0 1D 97 12 2A 6B 0C C5 B5 FF 34 03 BD B1 C5 BF
Data: AD 6F 26 86 AF 5B 9B 15 65 E1 2B 95 5F 4D 69 B6 88 E9 7A 2D DB 96 80
Data: AE 45 C9 1B 40 96 FF E3 B2 D9 93 54 43 DE 49 2B 93 57 3D F9 5C BD 8D
Data: A1 37 0B B9 64 EA 92 F5 E1 E3 C0 F0 43 45 9A 32 34 87 87 CF EB CD 5A
Data: A8 23 26 55 4C 98 C9 4C 71 03 86 C4 51 36 F9 B1 FB 30 FF 49 A5 CF 47
Data: AD 6F 26 80 29 E1 E5 6B 5B E7 2D D1 A3 B1 25 02 3C 9D E6 B9 42 2B A0
Data: AE 45 C9 15 C2 18 75 69 3C 5F 15 12 01 9C 97 D9 61 E9 DB 13 F7 87 4E

10101111 00000110 10010001 10001000 00010110 11101000 00000000 01001010 10100001 10000110 10110011 11000010 01001110 00111100 10000101 10101100 00110001 11111101 10100011 01000000 10101100 00101111 00000011 10100011 00101011 10111111 00100000 10001111 11101011 00011100 01101110 01101110 10101000 10010110 01010001 01110010 11111100 11100110 10111111 01101011 11100001 00010111 10011011 11001001 10111010 00011010 10100101 10101100 11010100 11100100 00000111 01011110 00001001 00111100 00100011 01000011 11011110 11110110 11011011 11100101 10100101 10000100 11010101 01101110 00001000 01111100 01010101 00010010 01011000 10100111 11101111 11110010 11000011 00110110 11100101 01010100 01110111 00001011 10010010 10010100 01111010 10000010 10011110 01100001 11101100 00100110 10111010 00101011 01001110 11000011 00000110 11110001 10101000 00100011 00100110 01010001 01010000 01111100 01100101 11100000 00011101 10010111 00010010 00101010 01101011 00001100 11000101 10110101 11111111 00110100 00000011 10111101 10110001 11000101 10111111 10101101 01101111 00100110 10000110 10101111 01011011 10011011 00010101 01100101 11100001 00101011 10010101 01011111 01001101 01101001 10110110 10001000 11101001 01111010 00101101 11011011 10010110 10000000 10101110 01000101 11001001 00011011 01000000 10010110 11111111 11100011 10110010 11011001 10010011 01010100 01000011 11011110 01001001 00101011 10010011 01010111 00111101 11111001 01011100 10111101 10001101 10100001 00110111 00001011 10111001 01100100 11101010 10010010 11110101 11100001 11100011 11000000 11110000 01000011 01000101 10011010 00110010 00110100 10000111 10000111 11001111 11101011 11001101 01011010 10101000 00100011 00100110 01010101 01001100 10011000 11001001 01001100 01110001 00000011 10000110 11000100 01010001 00110110 11111001 10110001 11111011 00110000 11111111 01001001 10100101 11001111 01000111 10101101 01101111 00100110 10000000 00101001 11100001 11100101 01101011 01011011 11100111 00101101 11010001 10100011 10110001 00100101 00000010 00111100 10011101 11100110 10111001 01000010 00101011 10100000 10101110 01000101 11001001 00010101 11000010 00011000 01110101 01101001 00111100 01011111 00010101 00010010 00000001 10011100 10010111 11011001 01100001 11101001 11011011 00010011 11110111 10000111 01001110

is your binary transulation. the words themselfs will need more formatting from my software but for now this might help.

Joined: 04 Mar 2008

If it is possible could someone upload another test dump or two and the .xml from the workout too?

Joined: 13 Mar 2008

This may help. I have a nike+ amp watch. This is holding the volume up button. As you can tell, lines should be exactly the same for this action, but are not. Indicating some byte manipulation is happening.

Code:

FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9D13,0122,BECC,6D
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,99F7,4F53,2003,9C
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,2626,7742,7BE6,5B
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,04A1,2F11,75FB,D3
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,6730,B5C7,E3A9,1B
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A961,67FA,7EB4,98
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EFCD,BFD8,ECD9,9D
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A0EE,DB5E,4195,B6
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,72E5,2F65,AEB2,13
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,762B,B60E,B58B,81
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6B73,6FE1,AFFE,A8
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,1611,32E6,F3F5,AF
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,1716,5C96,4153,1C
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EEC8,F6A7,28AD,F0
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E45,2230,358D,20
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,6313,C7C1,8AED,65
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9DF6,E4C7,592B,08
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,99E0,5844,3516,91
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,2632,6356,67FA,4F
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,04AD,231D,79F7,C7
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,674A,CFBD,9DD7,09
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A97B,7DE0,64AE,A2
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EFE7,95F2,C6F3,9F
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A008,3DB8,A377,9C
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,72FF,357F,B4A8,DD
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,7667,FA42,F9C7,4D
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6BAF,B33D,6B3A,D4
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,1664,4793,8086,7C
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,1763,29E3,3624,EF
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EEC9,F7A6,27A2,FB
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E46,2133,348C,1F
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,6314,C0C6,8BEC,66
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9DF7,E5C6,5A28,09
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,99F9,415D,2E0D,86
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,2628,794C,71EC,51
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,04A3,2D13,73FD,D1
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,6732,B7C5,E5AF,11
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A97E,78E5,5F95,BD
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EFEA,98FF,C9FC,80
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A01C,29AC,AF7B,98
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,7213,D993,5844,D1
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,7659,C47C,C3FD,57
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6BA1,BD33,6130,F6
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,163F,1CC8,D9DF,E5
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,1769,23E9,3C2E,D9
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EEC2,FCAD,22A7,F6
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E3F,584A,4BF3,5A
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,630D,D9DF,94F3,2B
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9D08,1A39,A3D1,5E
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,7210,DA90,5945,D4
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,7656,CB73,CAF4,5E
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6BBF,A32D,7B2A,E4
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,1657,74A0,B1B7,ED
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,175C,16DC,0715,4E
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EEC6,F8A9,26A3,FA
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E43,2436,2F97,16
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,6311,C5C3,88EF,67
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9DF4,E6C5,5725,12
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,99DE,667A,0724,6F
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,2632,6356,67FA,4F
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,04AD,231D,79F7,C7
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,673C,B9CB,E7AD,FF
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A96D,6BF6,72B8,94
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EFF1,83E4,D0E5,B9
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A012,27A2,BD69,B2
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,7209,C389,425E,F7
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,7670,ED55,ECD2,40
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6BB2,AE20,7021,07
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,1650,73A7,B4B2,F0
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,1766,2CE6,3123,EC
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EEBF,81D0,5DD8,E5
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E3C,5B49,4EF6,55
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,630A,DED8,91F6,30
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9D0A,183B,A5D7,54
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,99F4,4C50,2102,A5
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,2623,7247,78E5,62
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,049E,102E,48C6,3A
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,672D,A8DA,F8B2,FA
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A982,8419,9B51,81
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EFEE,9CFB,CDF8,7C
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A00F,3ABF,A276,93
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,7206,CC86,4B57,F2
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,764C,D169,D0EE,6C
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6B94,8806,5607,99
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,1632,11C5,D6D0,12
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,1737,7DB7,6270,7B
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EE90,AEFF,70F5,88
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E0D,6A78,7DC5,48
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,63DB,0F09,4225,1D
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9DBE,AC8F,1163,C0
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,99A8,100C,7D5E,B9
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,26D7,86B3,8C11,EE
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,0452,DCE2,840A,86
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,67E1,6416,347E,46
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A912,1489,0BC1,11
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EF7E,0C6B,5D68,0C
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A09F,AA2F,32E6,23
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,7296,5C16,DBC7,42
FF55,1E,09,0D0E10,01ACEB00,01,3D,8F,DF,FEF8,65E0,2A09,4397,A281,B481,9D7E,6C4F,D1A3,80
FF55,1E,09,0D0E10,01ACEB00,01,34,9B,9E,8EFC,9BAE,9B87,091B,5123,3FEB,9968,D0CC,BD9E,F9
FF55,1E,09,0D0E10,01ACEB00,01,3B,10,96,1520,A5B9,6D1F,823A,823A,F0EC,2697,C6F3,CC51,2E
FF55,1E,09,0D0E10,01ACEB00,01,32,05,18,4B81,CB01,1DD7,CB9A,4E1F,A799,0412,9CA2,C44A,C6
FF55,1E,09,0D0E10,01ACEB00,01,39,AE,7B,7FE2,5AE2,DC41,F977,F92D,7C2D,67A1,2456,743E,86
FF55,1E,09,0D0E10,01ACEB00,01,30,BB,DD,0B17,99C8,99D3,E663,FEEC,FEF8,A9D2,D449,CB01,D1
FF55,1E,09,0D0E10,01ACEB00,01,37,6A,D3,A380,5446,4011,3234,652F,FBE9,EF3E,4C2B,1D28,CC
FF55,1E,09,0D0E10,01ACEB00,01,3E,28,A7,C288,4296,8482,90E2,282E,A025,A05F,6AEF,F226,E3
FF55,1E,09,0D0E10,01ACEB00,01,35,17,2A,1628,79F7,72F7,7247,5BDE,D860,7256,9CD6,1B07,02
FF55,1E,09,0D0E10,01ACEB00,01,3C,D3,E7,2F48,5A5C,E4F6,A76D,E88F,C5A2,769C,01B9,003E,1C
FF55,1E,09,0D0E10,01ACEB00,01,33,53,71,3DE9,EFA5,C216,108D,FFE3,7E0C,6BE4,F876,2677,29
FF55,1E,09,0D0E10,01ACEB00,01,3A,80,9D,1507,24B9,CBAC,7864,62FF,8DAE,1682,A175,6660,62
FF55,1E,09,0D0E10,01ACEB00,01,31,61,14,8B33,2F5D,7EC6,B497,F03A,0499,1787,CD07,D2C0,CB
FF55,1E,09,0D0E10,01ACEB00,01,38,A9,64,7A2B,1E20,BD33,541E,0C39,5ED0,EEE0,DE8F,0085,58
FF55,1E,09,0D0E10,01ACEB00,01,3F,87,1B,A52B,1572,FCC2,FCC2,FCC2,E1AB,9E5D,3A28,2D95,F8
FF55,1E,09,0D0E10,01ACEB00,01,36,DC,97,A421,5370,3A0F,C5A2,810F,8A40,632B,FFF9,B2D5,CD

The commas are where I felt logical breaks were, and needed to load CSV in to a spreadsheet for column sorting to see how bytes lined up.

It is definitely not full encryption, since bytes +/- sequences do start to line up. I also feel that the first 2 possibly 3 of bytes in the payload (#13, #14, #15) influence's the rest of the bytes obfuscation. The bytes start to align with each other across lines, and seems to be some type of modulus, or odd/even pattern. It's not that hard to figure out, just haven't had time to focus on it.

When lines start to repeat, the last 6 bytes before checksum are still always different. Perhaps a time stamp, or jibberish.

Joined: 26 Apr 2008

I was reading a bit on here and I'm nowhere near as smart with this stuff as you guys are but I do know one thing and that is math. This is why I think the readout is counting steps and taking the time between them. I think the counting is taking place on the first section of each line. I'm thinking this because in the Nike+ you need to calibrate it by running a distance that is predetermined on the IPod. From this predetermined distance it will get the distance one step is for the individual.

amount of steps / distance said to run = distance per step

now with this information the Nike+ could, by simply counting the steps and duration between steps find out the distance, pace and time for the entire run. The only thing that's getting me puzzled is the IPod also determines calories burnt. This would be a function of the runners weight but I'm not too sure of the relationship between the two. I do know however that the runners weight is inputed when calibrating.

That being said I think the readout is containing,

- numbering of steps
- time between each step
- distance of each step (constant)
- weight of individual (constant)

- among other things I'm sure.

There might also be a separate file for the constants like a global header or something of that nature. I don't know just a thought

Hope this helps, or puts ideas in someone's head. You guys are doing a great job, keep it going.

//This is the readout I'm discussing about//

counting
line
|
|
V
AF AC CD 2A 92 4E 71 EC 5B 3C 3A C9 72 EF 3A F0 75 AE 79 35 3E D9 B6
A0 B3 69 55 76 0F 7E 19 C4 95 A0 A5 21 33 B1 8F AC 1F F9 01 8E E6 BA
A1 23 53 40 75 8F 5C 2E 07 39 4B A3 97 12 26 BB EA 86 A4 3B 78 6E 80
A2 6F 27 1A B8 E4 5D 4F 80 05 19 6A A1 75 6C 0B 96 D5 59 69 B7 C7 78
A3 4A 58 38 55 F6 3D 1E B3 90 44 64 5B 5D 4F 9B 89 51 B8 CC 6E 3A 9C
A4 37 16 36 AC A0 B3 B5 08 86 94 4E D4 9E 1C 6E 5B 85 85 53 8D AB 1B
A5 FD AE FA 74 3B B6 88 CF 1B 95 32 56 75 BB F1 96 2B 19 A3 1D 73 E6
A6 45 59 1F 41 38 6A 20 60 FD AC 44 91 1F F4 E8 EE 1A 8B 43 CC A6 CB
A7 1C 94 06 CA E0 C4 7C 3F 87 4D 95 E8 9A 04 27 6D 4E 86 96 FC 11 D2
A8 57 53 73 E9 4B 58 92 CB FE 99 F5 C0 91 C1 90 1E C7 8C 04 A6 E9 72
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AB EF DC BC 6D 0B 8F 0A 30 22 9A 70 22 3E C8 CE 04 F5 2B 39 5F CE 33
AC 78 B4 0B F9 02 49 7C 05 4F 05 3B 2A 4D 4C F4 20 CD 73 16 2E 0F B1
AD 2B 17 0E 5A 70 77 26 3C F6 C8 1F 92 58 F7 72 00 0E 27 14 74 A2 23
AE A1 3E 49 FC EA 78 F6 A8 DA F9 AD AC 92 D4 E1 DF 35 A7 24 0D 6F B2
AF AC CD 2A 12 D2 ED 70 C8 AF A9 56 EF 72 9F 55 D0 49 56 1E 97 6E 62
A0 B3 69 55 F6 93 E2 85 61 30 05 48 CE DC 56 68 4B 46 40 48 85 1F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 B6 AB 9F 83 ED F1 74 88 AC 99 28 A6 1E A9 C7 E6 CA 11 8D
AB EF DC BC ED 8B 0F 8A B0 A2 1A F0 A2 BE 48 4E 84 75 AB B9 DF 4E 33
AC 78 B4 0B 79 82 C9 FC 85 CF 85 BB AA CD CC 74 A0 4D F3 96 AE 8F B1
AD 2B 17 0E DA F0 F7 A6 BC 76 48 9F 12 D8 77 F2 80 8E A7 94 F4 22 23
AE A1 3E 49 7C 6A F8 76 28 5A 79 2D 2C 12 54 61 5F B5 27 A4 8D EF B2
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92
A9 C4 7E 84 82 F0 98 4C ED EB 76 33 30 88 10 02 1E 37 52 05 BB 0B D0
AA 06 85 D1 36 2B 1F 03 6D 71 F4 08 2C 19 A8 26 9E 29 47 66 4A 91 8D
AB EF DC BC 6D 0B 8F 0A 30 22 9A 70 22 3E C8 CE 04 F5 2B 39 5F CE 33
AC 78 B4 0B F9 02 49 7C 05 4F 05 3B 2A 4D 4C F4 20 CD 73 16 2E 0F B1
AD 2B 17 0E 5A 70 77 26 3C F6 C8 1F 92 58 F7 72 00 0E 27 14 74 A2 23
AE A1 3E 49 FC EA 78 F6 A8 DA F9 AD AC 92 D4 E1 DF 35 A7 24 0D 6F B2
AF AC CD 2A 92 52 6D F0 48 2F 29 D6 6F F2 1F D5 50 C9 D6 9E 17 EE 62
A0 B3 69 55 76 13 62 05 E1 B0 85 C8 4E 5C D6 E8 CB C6 C0 C8 05 9F 4E
A1 23 53 40 C5 01 D6 A4 92 AC DE 36 04 81 B5 28 79 F3 B9 26 14 CA DE
A2 6F 27 1A 08 36 8F 9D B3 36 2A 9D 58 8C 85 E2 7F 6E C2 FE CF 7F A0
A3 4A 58 38 A5 48 83 A0 52 71 A5 C5 FC FA F0 24 36 BC 0D 81 52 4E 6E
A4 37 16 36 FC 50 43 45 38 B6 A4 3E A4 EE 4C 3E 0B 35 15 C3 1D 3B FB
A5 FD AE FA C4 CB 46 78 7F AB 25 C2 A6 85 4B 01 66 1B 09 B3 0D 83 66
A6 45 59 1F 91 E8 BA F0 10 8D DC 74 A1 2F C4 D8 DE EA 5B 93 1C F6 AB
A7 1C 94 06 1A 90 B4 0C 8F 37 FD E5 98 EA 74 57 1D 7E 96 86 EC 21 D2
A8 57 53 73 39 1B 08 C2 1B 2E 49 25 70 21 71 20 AE 37 3C B4 F6 39 92

Joined: 05 Jun 2008

I recently ordered the sparkfun kit as well, and am working on decoding the undecipherable part of the hex string.

I found out that the receiver runs on the ANT networking protocol, but I'm unsure if we can extrapolate anything from it because of apple's user defined layer on top of ANT.