The bcdDevice field is a number value from the USB descriptor: Device release number in binary-coded decimal
| bcdDevice | # | % |
|---|---|---|
| 1.00 (firmware release?) | 84 | 33.07 % |
| 1.01 (firmware release?) | 11 | 4.33 % |
| 1.02 (firmware release?) | 11 | 4.33 % |
| 0.00 (firmware release?) | 9 | 3.54 % |
| 2.03 (firmware release?) | 9 | 3.54 % |
| 1.47 (firmware release?) | 7 | 2.76 % |
| 1.10 (firmware release?) | 6 | 2.36 % |
| 2.00 (firmware release?) | 6 | 2.36 % |
| 0.30 (firmware release?) | 5 | 1.97 % |
| 5.23 (firmware release?) | 5 | 1.97 % |
| 0.01 (firmware release?) | 4 | 1.57 % |
| 0.10 (firmware release?) | 3 | 1.18 % |
| 1.12 (firmware release?) | 3 | 1.18 % |
| 1.20 (firmware release?) | 3 | 1.18 % |
| 2.04 (firmware release?) | 3 | 1.18 % |
| 50.00 (firmware release?) | 3 | 1.18 % |
| 0.08 (firmware release?) | 2 | 0.79 % |
| 0.50 (firmware release?) | 2 | 0.79 % |
| 1.08 (firmware release?) | 2 | 0.79 % |
| 1.11 (firmware release?) | 2 | 0.79 % |
| 1.19 (firmware release?) | 2 | 0.79 % |
| 1.71 (firmware release?) | 2 | 0.79 % |
| 1.72 (firmware release?) | 2 | 0.79 % |
| 12.01 (firmware release?) | 2 | 0.79 % |
| 2.10 (firmware release?) | 2 | 0.79 % |
| 20.01 (firmware release?) | 2 | 0.79 % |
| 3.00 (firmware release?) | 2 | 0.79 % |
| 5.00 (firmware release?) | 2 | 0.79 % |
| 5.10 (firmware release?) | 2 | 0.79 % |
| 5.25 (firmware release?) | 2 | 0.79 % |
| 6.00 (firmware release?) | 2 | 0.79 % |
| 61.23 (firmware release?) | 2 | 0.79 % |
| F0.F0 (firmware release?) | 2 | 0.79 % |
| 0.02 (firmware release?) | 1 | 0.39 % |
| 0.03 (firmware release?) | 1 | 0.39 % |
| 0.05 (firmware release?) | 1 | 0.39 % |
| 0.06 (firmware release?) | 1 | 0.39 % |
| 0.13 (firmware release?) | 1 | 0.39 % |
| 0.38 (firmware release?) | 1 | 0.39 % |
| 0.40 (firmware release?) | 1 | 0.39 % |
| 0.96 (firmware release?) | 1 | 0.39 % |
| 0.99 (firmware release?) | 1 | 0.39 % |
| 1.03 (firmware release?) | 1 | 0.39 % |
| 1.04 (firmware release?) | 1 | 0.39 % |
| 1.06 (firmware release?) | 1 | 0.39 % |
| 1.16 (firmware release?) | 1 | 0.39 % |
| 1.17 (firmware release?) | 1 | 0.39 % |
| 1.21 (firmware release?) | 1 | 0.39 % |
| 1.24 (firmware release?) | 1 | 0.39 % |
| 1.50 (firmware release?) | 1 | 0.39 % |
| 1.57 (firmware release?) | 1 | 0.39 % |
| 1.60 (firmware release?) | 1 | 0.39 % |
| 10.00 (firmware release?) | 1 | 0.39 % |
| 11.63 (firmware release?) | 1 | 0.39 % |
| 2.01 (firmware release?) | 1 | 0.39 % |
| 2.02 (firmware release?) | 1 | 0.39 % |
| 2.05 (firmware release?) | 1 | 0.39 % |
| 2.06 (firmware release?) | 1 | 0.39 % |
| 2.07 (firmware release?) | 1 | 0.39 % |
| 2.11 (firmware release?) | 1 | 0.39 % |
| 2.13 (firmware release?) | 1 | 0.39 % |
| 2.21 (firmware release?) | 1 | 0.39 % |
| 2.71 (firmware release?) | 1 | 0.39 % |
| 3.01 (firmware release?) | 1 | 0.39 % |
| 3.02 (firmware release?) | 1 | 0.39 % |
| 3.10 (firmware release?) | 1 | 0.39 % |
| 5.02 (firmware release?) | 1 | 0.39 % |
| 5.08 (firmware release?) | 1 | 0.39 % |
| 5.18 (firmware release?) | 1 | 0.39 % |
| 5.21 (firmware release?) | 1 | 0.39 % |
| 5.22 (firmware release?) | 1 | 0.39 % |
| 5.30 (firmware release?) | 1 | 0.39 % |
| 5.34 (firmware release?) | 1 | 0.39 % |
| 52.57 (firmware release?) | 1 | 0.39 % |
| 6.07 (firmware release?) | 1 | 0.39 % |
| 6.27 (firmware release?) | 1 | 0.39 % |
| 6.32 (firmware release?) | 1 | 0.39 % |
| 61.10 (firmware release?) | 1 | 0.39 % |
| 7.27 (firmware release?) | 1 | 0.39 % |
| 7.36 (firmware release?) | 1 | 0.39 % |
| 9.14 (firmware release?) | 1 | 0.39 % |
This field is the firmware release number. So it can be realy anything. The most common value is 1.00. But you can also find strange values as F0.F0 are also possible.