Any way to expand the number of digital ports

Connectivity BLE // NFC
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Really excited for this to come out and i was about to preorder, but then i did an inventory of how many digital pins that i will need for the proposed project and saw that i need a minimum of 13 for one of the devices… (https://www.adafruit.com/product/607)

is there anyways to get more digital pins out of this device potentially (looks like its expanded to 8 from the photons 7)? I know i saw https://docs.particle.io/reference/firmware/photon/#digitalwrite- but not sure if this will also apply or not since I cannot get my hands on one yet and didn’t see anything about that in what i could find on the mesh?

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Most of the pins on the nRF52840 can be used as GPIO. So, for example, if you don’t need SPI, I2C, or Serial, all of those pins can be used for GPIO.

And if you need a huge number of GPIO, you can always use the MCP23017 which adds 16 GPIO by I2C. And you can add 8 of them off the I2C bus, in case you need 128 GPIO.

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@rickkas7 Sexy! looks like i know what i will be pre-ordering…

the final thing I am trying to confirm, is will the Argon (and also photon) be able to work with with this:

ProductPage - https://shop.openbci.com/collections/frontpage/products/cyton-daisy-biosensing-boards-16-channel?variant=38959256526
DocsPage - http://docs.openbci.com/Hardware/02-Cyton

its listed as arduino compatible, but then also seems to be already pre loaded with what i need, so i don’t see why you would need to hook it up to an arduino board … (i do have an email out to them as well but i figured it wouldn’t hurt to ask you guys also as I am not that well versed in the IoT hardware side of things so trying to figure this out and verify compatibility is a bit confusing…

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Are you aware that the Photon actually features 18 GPIOs all of which can be used as digital IO pins (if not actively used otherwise)?

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@ScruffR, no i did not… and seeing as they are marked A_ and D_ on the boards was the starting place for that lack of knowledge…

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The problem is that the silk screen doesn’t allow for all possible features to be printed on.
But the datasheet does tell
https://docs.particle.io/datasheets/photon-(wifi)/photon-datasheet/#peripherals-and-gpio
https://docs.particle.io/datasheets/photon-(wifi)/photon-datasheet/#pin-description

The A# merely states that these pins are analogRead()able but doesn’t limit to that.

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hmm okay, reading those two links for someone who is not a hardware guy, leaves some ambiguity.

you say there are 18 that can be used as digital of the 24 pins of the photon. looking at https://docs.particle.io/datasheets/photon-(wifi)/photon-datasheet/#pin-description it seems that all but 3V3, the 2 GND, VIN, VBAT and RST (whivh i thought was the same as the RESET button on the device at first) are the ones that can’t be used as digital…

its too bad they cant be color coded based on what they can do + the names like the led that tells the device state as that is a lot less confusing when working with abbreviations and what they mean. (i.e. have color strip like D7 is based on configuration and then in white or black have the text label that is printed on the devices currently. I know it adds cost compared to just the blue ink all over, but it would go a long way to help less technical people understand the complexities of the photons and not need 20+ web browser tabs all with the same icon on them to figure things out (yes bookmarks also help but that’s a different discussion)