NFC add-on

[DrYak]

Has somebody an idea if it would be possible to solder-in some support for NFC?
(e.g.: so the watch could communicate with continuous glycaemia monitors like this, for which there is already opensource code available)

[wibble]

Unfortunately the pins required for NFC are being used for other things.
http://files.pine64.org/doc/PineTime/Pin...191103.pdf
https://infocenter.nordicsemi.com/index....2Fpin.html

[lupyuen]

Yep that's correct, the conflicting pins are P0.09 and P0.10.

For Mynewt OS we have configured the two pins as GPIO pins instead of NFC pins...

https://github.com/lupyuen/pinetime-rust...ml#L51-L52

That's because the pins are used by the display and touch controllers according to http://files.pine64.org/doc/PineTime/Pin...rev1.0.pdf

P0.09 / NFC1: LCD_DET (OUT)

P0.10 / NFC2: TP_RESET (OUT)

FYI NFC1 and NFC2 pins are for connecting the NFC antenna, see https://infocenter.nordicsemi.com/pdf/nR...S_v1.0.pdf

[DrYak]

You mean that the chipset used in PineTime can straight up do NFC itself (no extra controller required) when connected an antenna to pins 9 and 10?

Hmm.... My idea might be completely bonkers (Dr "Bones" McCoy's voic: I'm a doctor, Jim! No an RF antenna engineer) but would be possible (with the help of either a MUX chip or physical switch) to alternate between driving the screen or the antena?
i.e.: display turns off, use antena, NFC transaction finishes, antenna shuts off, diplay turns back on ?

[lupyuen]

Yep nRF52832 is NFC capable, just that it's not wired that way for PineTime.

Check out the docs for nRF52832: https://infocenter.nordicsemi.com/pdf/nR...S_v1.0.pdf

[DrYak]

So could a switch hot wired to another free GPIO pin be used between display and antenna ?

[lupyuen]

Hmmm not sure...

Sent from my Pixel 4 XL using Tapatalk

[danielt]

So could a switch hot wired to another free GPIO pin be used between display and antenna ?

Are you looking for a board respin or a wire mod?

It is possible to tweak the code running on the watch so that both LCD_DET and TP_RST are unused (the touch panel works OK without TP_RST but it is not possible to put it into a power saving mode).

That might make a wire mod possible although it will be mechanically difficult to pull off!

Reading the schematic I think you'd need to disconnect TP_INT and LCD_DET by jamming something into the connectors (or punching a tiny hole in the ribbon cable), desolder R25 and R30 and then use the resulting exposed pads to connect the NFC antenna.

[mitcoes]

If PineTime becomes a NFC watch for payments it would increase a lot sells.

Please make it work, and I am sure, as it would be the cheaper "payment method in a watch with NFC" some credit and debit cards companies, or payment methods companies would sponsor the development and make high volume buys after that to sell or even give to their customers PineTimes to make payments.

I would buy PineTime with NFC for payments, and order it just now, but not actual PineTime, and I am waiting for a cheap NFC wristband or watch to appear in the market to buy it, as I suppose many other prospects.

[wibble]

Unless you can get the banks on board it can't happen. Given their reaction to rooted Android phones I don't see them supporting a phone where the user can rewrite the firmware.