Increase PN532_PACKBUFFSIZ to 128 bytes
#132
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This change is in response to a bug in this library found when working with NFC YubiKeys, which contain an NDEF record that is returned as 71 bytes (6 bytes of header, 63 bytes of payload, 2 bytes of status words). It was found that when read using `inDataExchange()`, the last 15 bytes (13 bytes of payload and 2 bytes of status words) are being read as `00` rather than their actual value: ``` 00 43 D1 01 3F 55 04 6D 79 2E 79 75 62 69 63 6F 2E 63 6F 6D 2F 79 6B 2F 23 76 76 63 63 63 62 69 63 75 6C 75 63 6A 6A 6E 67 6B 75 69 62 75 62 6E 74 6A 65 63 68 76 6A 66 00 00 00 00 00 00 00 00 00 00 00 00 00 ``` However the reading function still returns true as though it succeeded. This has been documented [here](esphome/feature-requests#2207 (comment)), and a suggested solution is to increase the size of `PN532_PACKBUFFSIZ`. Although I'm not sure what the optimal size is, upping it to 128 solved my problem but is not wildly larger (given this is obviously meant for am embedded system).
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This change is in response to a bug in this library found when working with NFC YubiKeys, which contain an NDEF record that is returned as 71 bytes (6 bytes of header, 63 bytes of payload, 2 bytes of status words).
It was found that when read using
inDataExchange(), the last 15 bytes (13 bytes of payload and 2 bytes of status words) are being read as00rather than their actual value:However the reading function still returns true as though it succeeded.
This has been documented here, and a suggested solution is to increase the size of
PN532_PACKBUFFSIZ.Although I'm not sure what the optimal size is, upping it to 128 solved my problem but is not wildly larger (given this is obviously meant for an embedded system).