Distinguished gentlemen, 
first of all, please let me congratulate you for the excellent work you did with Pixy, as it resulted in a really nice piece of engineering. Thanks for sharing it with us all in the form of open source hardware and software!
I’ve been studying Pixy’s hardware documentation and found some discrepancies between the the BOM, schematic diagram and what is actually mounted on my Pixy board (v1.3). I will list below what I found with two main intentions: a) perhaps it will be useful for you to update the documentation (if that is the case); and b) to understand why these modifications were made.
Here are the discrepancies I found:
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R23 (10.0k) is missing from the BOM.
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D2 (MSS2P2) appears in the schematic diagram, but is not mounted in my Pixy 1.3 and neither listed in the BOM.
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R10 (4.7k) appears both in the schematic diagram and the BOM, but is not mounted in my Pixy 1.3. Is there no need for a pull-up resistor for the CAM_SIOD signal?
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R18 and R20 are listed as 4.7R resistors in the BOM, appear as 4.02R resistors in the schematic diagram, but are actually mounted as 1.2R resistors in my Pixy 1.3 (I could only notice this because these are “large” 1W resistors with their values printed on them). Do you think there might be any other component values that may have changed from version 1.2 (I’m guessing from the schematic file name) to version 1.3?
Additonal comments and questions:
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In the schematic diagram, the part value of C17 (0.1uF) is shifted towards R13 and therefore is somewhat “hard” to find.
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Are L1 and L2 really mounted as 3.3uH inductors as listed in the BOM? Unfortunately, the schematic diagram doesn’t mention their part values and this information can’t be cross-verified.
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What kind of JTAG ICE would you recommend to attach to J5 if one wishes to develop firmware using this kind of tool?
Thanks in advance,
Hugo