After PCD_PerformSelfTest() card can`t be read

[saloid]

Step 1: Describe your environment

• OS version: Win 10
• Arduino IDE version: 1.9.0-beta
• MFRC522 Library version: 1.4.0 (from arduino library manager)
• Arduino device: Nano
• MFRC522 device: RFID-RC522 (blue board)

Step 2: Describe the problem

After using PCD_PerformSelfTest() I should init (call PCD_Init()) module again, because without this it doesn't reads cards (PICC_IsNewCardPresent() always returns "false").

Maybe it will be better to init module again inside selftest function?

Relevant Code:

doesn`t works:

  rfid.PCD_Init();
  Serial.println(rfid.PCD_PerformSelfTest() ? "ok" : "ERROR!");

works:

  rfid.PCD_Init();
  Serial.println(rfid.PCD_PerformSelfTest() ? "ok" : "ERROR!");
  rfid.PCD_Init();

[Rotzbua]

Thanks for using the issue template :+1:

  rfid.PCD_Init();

Makes a reset. So everthing should work no matter what PCD_PerformSelfTest() makes wrong :)

I guess the selftest function of the library does not unset the selftest mode. The datasheet says:

Remark: for default operation the self test must be disabled by value 0000b

[HenrikSte]

Thanks for posting this. Spent an hour to find out why I am not reading anything... Adding a init after self test fixed it.

[fmuntean]

Same issue here: the SelfTest is leaving the board in an unusable state until init is called again.