I have been trying to detect an tag using the PN532 module that I bought from amazon here:
https://www.amazon.ca/ASHATA-Controller-Raspberry-Interface-Switching/dp/B07XFNDHNS
I followed the tutorial here:
http://wiki.sunfounder.cc/index.php?title=PN532_NFC_Module_for_Raspberry_Pi
I tried using both I2C or SPI, but both results just give me the following when I run nfc-poll:
nfc-poll uses libnfc 1.7.1
NFC reader: pn532_spi:/dev/spidev0.0 opened
NFC device will poll during 30000 ms (20 pollings of 300 ms for 5 modulations)
nfc_initiator_poll_target: Success
It seems like the PN532 is connected to the Pi properly, but the tag is not being detected or printing any info. I am beginning to wonder if the problem is with the PN352 device itself. Maybe I got a faulty one?
Thanks
Answer
Update 2020mar29hkt2040
Part 1 - libnfc v1.17 I2C config tested OK
The OP has no luck in testing libnfc I2C mode and SPI mode. I tried I2C mode and found everything OK. I guess the OP has not set the config file, or has not set "auto scan = true". See my example libnfc171 config file in Appendix A. PS - (1) My NFC reader can detect a tag without any problem. (2) I am using Rpi4B buster 2020mar13.
Part 2 - Now testing SPI mode 2020mar29hkt2044
Sunfounder config instructions recommends lowering SPI speed 50kHz. So I have changed the /bbo/config.txt file as shown in Appendix F.
/ to continue, ...
References
(1) The OP's NFC RFID Controller Module
(2) SunFounder Rpi PN532 NFC Module Tutorial
(3) Libnfc NFC Library
(4) Libnfc Configuration Manual
(5) Libnfc Main Page
(6) Libnfc: configuration
(7) Libnfc: nfc-list
(8) MIFARE Card
Appendices
Appendix A - Installing libnfc 1.7.1
Appendix B - Reading a tag
Appendix C - NFC Reader Tested
Appendix D - My NFC readers and tags
Appendix E - PN532 NFC reader V3 Wiring
Appendix F - SPI configuration for testing PN532 using libnfc 1.1.7