NFC code not working

[Gordon]

Hi,

I'm trying to get NFC working on a PCA10040 dev board. Using the nfc/record_url hex file it works fine, so the hardware is obviously ok.

However, when I use the exact same code as in the record_url example from my software, it doesn't do anything. All functions execute without errors, but then log_uart_printf gets called with:

[NFC_HAL]: initialize
[NFC_HAL]: start
// ------------- put NFC device near 
[NFC_HAL]: fielddetected
[NFC_HAL]: reinitialize
[NFC_HAL]: fielddetected
[NFC_HAL]: fielddetected
[NFC_HAL]: reinitialize
[NFC_HAL]: fielddetected
[NFC_HAL]: reinitialize
[NFC_HAL]: fielddetected
[NFC_HAL]: reinitialize
[NFC_HAL]: fielddetected
[NFC_HAL]: fielddetected
[NFC_HAL]: fielddetected
[NFC_HAL]: fielddetected
[NFC_HAL]: reinitialize
[NFC_HAL]: fielddetected
[NFC_HAL]: reinitialize

Also, will the NFC code ever be distributed as something that's not a binary blob? I'm using a language interpreter (Espruino), and it expects functions to be compiled without hardware floating point (the call style is different). Currently the only way I can use NFC is to recompile with VFP, which means I'm then unable to pass floating point values into any functions!

[Hung Bui]

@Gordon: you can have a look at the experimental_ble_app_hrs_pairing_nfc example. It's the example with NFC and softdevice.

The NFC code will be precompiled binary at least for now. I don't think we have plan to have it open source soon.

[Gordon]

Hi - thanks for the answer. I did see experimental_ble_app_hrs_pairing_nfc and tried to copy it before posting (but I don't see anything different that would apply to PCA10040). I edited my question above with the results from log_uart_printf - hope that helps somehow?

[Hung Bui]

Hi Gordon,

Attached is an example to use record_url in other example (ble_app_hrm). I don't see any issue. Could you try ?

ble_app_hrs_URL_nfc - Copy.zip

[Gordon]

I've copied that code into my project in the same place and it's not working (same error messages as above) - however if I use the hex file for (for example) experimental_ble_app_hrs_pairing_nfc then it works.

What could be causing it not to work from my software? Does it use any extra hardware that my software might be messing with? I've made sure to disable sd_app_evt_wait and TIMER1 usage just in case.

[Hung Bui]

@Gordon: I saw the same log if I don't put the phone close enough to the NFC antenna. It seems that the field was not strong enough for the NFC to send data and causing it to reinitialized. But if I put the phone close enough tx and rx were managed to send.

My suggestion is to start first with just the NFC and comment out everything else, then you can gradually add more functionality back until you see the problem.