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在Mifare DESFire卡上格式化PICC会使它失效吗？

[英]Format PICC on Mifare DESFire card makes it useless?

原文 2012-12-22 17:59:27 4 2 android/ nfc/ mifare

I am working on Mifare DESFire 4k tags on android, using the IsoDep and DESFire native commands. 我正在使用IsoDep和DESFire本机命令在android上处理Mifare DESFire 4k标签。 When I send a PICC Format command to the card, I get a TagLostException and after that the tag is no longer detectable using any software on Android. 当我向卡发送PICC格式命令时，我得到TagLostException，此后使用Android上的任何软件都无法检测到该标记。 Is this the expected behavior? 这是预期的行为吗？ Is there a way to get the tag to behave as it did before the format? 有没有一种方法可以使标记像在格式化之前一样起作用？

2 个解决方案

Try increasing the transceive time-out before sending the format command, using setTimeout() , to some large value (a couple of seconds). 在使用setTimeout()发送格式命令之前，尝试将收发超时增加到某个较大的值（几秒钟）。 Formatting a DESFire tag takes some time. 格式化DESFire标签需要一些时间。 I had the same experience with the TagLostException, but have never ruined a tag... 我对TagLostException有相同的经验，但从未破坏过标签...

I rather agree with NFC guy. 我更喜欢NFC的家伙。 It's very rare to ruin a tag when formatting PICC but no so uncommon to receive TagLostException when operating with tag due to Android code (known bug/issue), Sometimes tag stops responding, but it should return to live after some time. 格式化PICC时破坏标签非常少见，但由于Android代码（已知的错误/问题），使用标签进行操作时，接收到TagLostException并不少见，有时标签会停止响应，但一段时间后它应该会恢复活动。