How to get NFC working?

[ulrichard]

I flashed the firmware out of the lnbits plugin, it says "BitcoinTaps PartyTap (version 827652 ) "
Looking up the PINS in https://forum.arduino.cc/t/esp32-sunton-esp32-3248s035-i2c/1188634 I connected the I2P pins of the NFC reader to GPIO21 and GPIO 22.
The NFC reader is : https://www.alibitress.com/item/1005006162306429.html

I can generate QR code invoices on the device, but when I hold my BoltCard to the NFC reader, nothing happens.
Could it be that version 827652 is too old for NFC?

[pieterjm]

Version 827652 does not have NFC support. For that you need version 834087 or higher.

In addition to that, to get NFC completely working, you'll need an additional component that converts I2C to servo signals. At this time of writing, I did not publish the details of that component. That will be soon (TM). It basically consists of an ATTiny that bridges I2C to servo signal. I'm working on a small PCB that contains all required components and connectors that make building the device a bit easier.

A prototype is shown in the screenshot below.

[ulrichard]

Thanks for the infos.
I want to use it for a candy grabber. For this I don't need a servo, but a simple digital pin output is enough. If this digital signal could be provided at GPIO35 on the other connector, then I wouldn't need the ATTiny.

[ulrichard]

@pieterjm I saw that the current firmware has NFC support, and allows the user to select different actuator modes. But "Relay, Time" uses pin 21 for the relay, and in this mode the NFC reader is not initialized, most likely because of the conflicting pin.
Is there a reason why pin 35 could not be used for the relais, and thus freeing up the I2C bus for reading from NFC?

[pieterjm]

To my knowledge GPIO35 is an input-only pin

[ulrichard]

Ah too bad. What about one of the UART pins that are exposed on the third connector. Could one of them be used for the relais, when disabling the UART?

[pieterjm]

I looked into that and it is not really an option. Sorry

[ulrichard]

@pieterjm Did you publish the code for the ATTiny in the meantime?