PN532 NFC module analog inputs

Lynxmotion Electronics & Software
1

Hi,

For a project I’m working with NFC and a BotBoarduino. My issue is that the board somehow doesn’t recognize the NFC module.

Here’s my setup:

  • This PN532 module is the NFC module, set to I2C mode with the flip switches
  • I’m aware that in order to use the I2C inputs I need to install the jumpers along SDA-P and SCL-P (as per the manual, point 12).
  • I am also using the Arduino IDE (version 1.8.1) with all necessary header files for this module.

I’ve used this BotBoarduino in the past with LEDs, Servos, and Buttons, and in the Arduino IDE I had to set the board to Duemilanove in Tools>Board. I noticed that the Arduino Due has SDA and SCL on pins 20 and 21 respectively, according to the Wire Library. HOWEVER, in the BotBoarduino manual, point 12, it says that configuring I2C will bring out A4 and A5.

Here’s where I’m stuck:
I have a feeling that the Wire Library is setting the input pins to 20 and 21 because the board is set to Duemilanove, but it really should be reading from A4 and A5. With that being said, is there a way to reconfigure the pins? I was researching something about an Arduino Core Variant file but I wasn’t too sure if that would solve my problem. I wanted to ask if anyone already has a board configuration that they wouldn’t mind sharing.
Also, if anyone notices something wrong with the way I set everything up, I’d be happy to hear it.

Thanks in advance

2

Hi,

The Arduino Duemilanove/BotBoarduino and Arduino Due are two different boards.
The I2C pins on the Arduino Duemilanove are located on pin A4 (SDA) and pin A5 (SCL) as on the Arduino UNO board. On the Arduino Due, the I2C pins are pin 20 (SDA) and pin 21(SCL).

Regards,

3

Thanks for your reply. I didn’t realize that the Due and Duemilanove were two different boards, thanks for pointing that out to me.

With that being said, would it mean despite the Arduino IDE set to Duemilanove, the libraries will interact with the board like its UNO?

4

That’s correct. Take a look at this project interfacing an Arduino Duemilanove and an IMU through I2C using the Wire library.

Regards,