Adding AttennaOff and get/set of AntennaGain

[mdxs]

Implementation for changing the MFRC522 Receiver Gain (RxGain) as discussed in #43. Allowing the Sketch to change the detection/interaction range (distance at which the PCD can interact with the PICCs).

Adding the following functions:

• PCD_GetAntennaGain() - Get the current MFRC522 Receiver Gain (RxGain[2:0]) value.
• PCD_SetAntennaGain() - Set the MFRC522 Receiver Gain (RxGain[2:0]) to given mask.
• and also (just to complement the above and the already existing PCD_AntennaOn():
  • PCD_AntennaOff() - Turns the antenna off by disabling pins TX1 and TX2.

Where RxGain[2:0] is configured via the RFCfgReg register as described in 9.3.3.6 / table 98 of the datasheet at http://www.nxp.com/documents/data_sheet/MFRC522.pdf

To support the Sketch developers, a PCD_RxGain enum is added to define the allowed values for RxGain[2:0] (a 3 bit pattern within the RFCfgReg register). Note that 9.3.3.6 of the datasheet shows that the RFCfgReg register has some reserved bits as well.

[omersiar]

Nicely done

[miguelbalboa]

Thank you

[Netoperz]

Hello, stupid question... where can i find a proper example how to use / set the antenna gain in sketch code ?

[foobar76]

@Netoperz I just looked in the suggested pdf Table 98

Serial.println(mfrc522.PCD_GetAntennaGain()); // gives me a 64 (00000010)
mfrc522.PCD_SetAntennaGain(112); // set to max (00001110)
Serial.println(mfrc522.PCD_GetAntennaGain()); //gives me the 112

Afterwards, I can see the demo card getting read from a significant bigger distance.

If anybody can tell me, why me NTAG216 implant is still not corresponding, your'e welcome :)

[martinius96]

@Netoperz I just looked in the suggested pdf Table 98

Serial.println(mfrc522.PCD_GetAntennaGain()); // gives me a 64 (00000010)
mfrc522.PCD_SetAntennaGain(112); // set to max (00001110)
Serial.println(mfrc522.PCD_GetAntennaGain()); //gives me the 112

Afterwards, I can see the demo card getting read from a significant bigger distance.

If anybody can tell me, why me NTAG216 implant is still not corresponding, your'e welcome :)

so, 112 is max value for gain? or 255 is max?