Problem with IRQ pin PN532

[Kalchev]

Hello guys,

I just got Adafruit PN532 board v1.3 . I`m trying to communicate with the chip via SPI and I want to use IRQ pin. When I just initialised SPI and CS pin is in high level (no commands are sent), the IRQ pin is in low state permanently. Also the busy LED is OFF. If I initialised SPI (CS low) and send GetFirmwareVersion command, the IRQ pin is going low for a 750ms. Is that normal? If you need some additional information, please feel free to ask me. Thanks in advance!

PS:
1. I`m using PIC24F(3.3V), not arduino.
2. The jumpers are closed.
3. The connections are:
PIC MOSI - MOSI PN532
PIC MISO - MISO PN532
PIC SCK - SCK PN532
PIC SS - SS PN532
PIC GPIO - IRQ PN532
PIC 3.3v - 5V PN532
PIC GND - GND PN532

[adafruit_support_rick]

You're using the PN532 shield? I don't think the breakout has the BUSY LED.

IRQ is normally low. It goes high when you read a card.

[Kalchev]

I`m using this product https://www.adafruit.com/products/789. There is a busy LED on the board. So the IRQ pin idle state is LOW, right? I`m not sure when exactly the IRQ pin and busy LED changes their state. Can you explain more about that please.

[adafruit_support_rick]

IRQ drives BUSY though a MOSFET. IRQ LOW will light the BUSY LED. When you read a card, you'll see the BUSY LED flash - that is because IRQ goes HIGH when a card is read

[Kalchev]

Ok, I`ll check that when I`m at home. So the IRQ is going HIGH after a card is being read, but also when I send correct GetFirmwareVersion command(or any other command), right?

[adafruit_support_rick]

Yes, I believe so.