PN532 pin RSTOUT_N

[frank55]

I connected the RSTPON pin (26) to ground via a BJT (BC547B npn) driven by an Arduino pin. I would like to know if I can leave this pin connected to ground for an indefinite time (for example a month) without creating problems.

PN532 pcb

http://osoyoo.com/2017/07/19/pn532-nfc-rfid-module-for-arduino/ 

pin of reference

[frank55]

but on aliexpress it is the cheapest version, for a hobbyist like me.
I also saw a schematic from adafruit that the same pin is connected to vpp via a 10k resistor.
why if it's only outgoing?

https://learn.adafruit.com/assets/26820 

[EduardoZamora]

Hi,

I think you are referring to Pin 38 - RSTPD_N, is this correct? If so, this input pin is active low; when this pin is set to logic 0, the PN532 goes into Hard Power Down (HPD) mode. The PN532 goes into reset and the RSTOUT_N signal is driven low.

For more information on this, please refer to PN532 Data Sheet, Section 8.5.2 Reset modes and Section 8.5.5 Low power modes.

Regards,
Eduardo.

[frank55]

Yes, I think it's pin 38 I'm referring to, as you can see from the png image, which I attached to the first post.
I must have gotten the pin numbering wrong.

so can I ground it directly?
Thank you

[EduardoZamora]

Hi,

You could set this pin to 0 to put the device into Hard Power Down mode as described in Section 8.5.5.

Regards,
Eduardo.

[EduardoZamora]

Hello @frank55

Hope you are doing well.

Please, consider that PN532 is Not Recommended for New Designs and our support for this device may be limited. For new designs, we recommend using PN7160.

From the PN532 Data Sheet, Chapter 7 Pinning information, pin 26 corresponds to RSTOUT_N, which is an output pin used to indicate the reset status. However, since it seems that this product is from a third-party, I will recommend you contacting the manufacturer for further support on this part.

Regards,
Eduardo.