PN532 Breakout / I2C Library

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karl_nottkarl
 
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PN532 Breakout / I2C Library

Post by karl_nottkarl »

I was looking at the Adafruit_NFCShield_I2C code, and in Adafruit_NFCShield_I2C.cpp::wirereaddata() there's a comment about discarding the leading byte, however, the code appears to not only do that, but also pick up an extra byte in the process.

The PN532 happily provides additional bytes on demand, in the case of an ack frame, an extra 0x02 that's discarded. I was just wanting to know if this was an oversight, or if some behavior had been discovered with the board that led to reading the additional data off the wire.

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Karl

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ktownsend
 
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Re: PN532 Breakout / I2C Library

Post by ktownsend »

Karl:

This is almost certainly an oversight. I'll have to pull a board out and test before I can commit any changes, but there is definitely no strange behavior that we're compensating for reading an extra byte.

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