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Expansion Board Demo (for 3.2" Enhanced Display)

Nothing exciting but makes use of all GPIO functions on Expansion Board.

Shows time, allows adjusting seconds, and setting display brightness.


The file should be named 3.2inchExpBoardDemoV1.3.HMI NOT 2.3inchExpBoardDemoV1.3.HMI.


Hello, did you saw any information about how we can use this expansion board?


The expansion board connects something to the eight digital gpio lines of the Enhanced Nextion

One LED - usually blinking an LED is the Hello World of MCUs

1 Buzzer - pin high (beep) ... pin low (silent)

6 buttons - so how to push a button?

Not sure what other information there is to be had - price of $5.00 USD.

What use it has relies solely on your programming skill.

You can buy a lot of components for under $5 and still have money for lunch.

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Sorry Patrick, you are right. I did not saw the information about the board in the Wiki page I suggest you to put this link or configuration info in the product page. Thank you 

Temporarily ignoring the fact that users are unable to put their links into things like the Instruction Set:

What use would that be?  The expansion board is a fancy proto-board turned pcb with a few resistors, caps, two regulators, a buzzer, led, and six buttons and a 10 pin fcc.  This like any other button, sensor, light, meter, for any other protoboard or pcb can be connected to what ever project.  There is no programming to be had on the expansion board itself and therefore there are no Instruction Sets.

If It is used with an ATMega or a Raspberry Pi or even a PIC, the programming skill needed to make use of any button, sensor, led, etc - is dependent to the platform it is being used on and the user who put it into their project. 

As an example, the old video games use to cycle through the alphabet using a joystick so users could put their name into the high scores.  This expansion card could be used for that purpose - as the buttons are labeled on the silk as up down left and right.  But this could also be used to control a dual axis servo requesting the direction the servos are pointing be adjusted up or down from its current position.  Another user has an Amateur Radio project going that it could be used for bands and frequencies, although it would most certainly be more awkward.

But just because the silk says UP, DOWN, LEFT and RIGHT doesn't prevent someone from using the six buttons in a PWM LED to add/subtract more RED, less GREEN, and more BLUEs.

The purpose is therefore decided by the integrator - and in order to integrate it into their project will require their programming skills to do so - on whatever platform they are working with.  The 10 pin flex cable connectors are becoming more common place and very inexpensive to acquire.  Soldering skills need be a bit finer.  With that said, The expansion board could be added to any project just as any sensor could be added, or a touch pad, or NFC reader.

Personally, I don't think that just because a nut and bolt could be used in building a particular structure, that one should now link to a single set of building plans.  Nor do I think that within a building plan, it links to all the possible paints and stains that could be used to coat the interior and exterior.  If the one link was to be included because "this could be used with the Nextion", why does that item get special privilege and not every mcu that has much better capabilities via serial communications?


All the items in Electronic-Components, Prototyping, Dev Platforms and Wireless that are able to be used in connection with someone's Nextion project are equally entitled for a link (as sold by Itead Studios), but then why not DigiKey, eBay and Taobao?

Because Itead sould this board and put this title "Expansion Board For Nextion Enhanced Display I/O Extended", and yes, it could be use in other project with any mcu etc.. but it the company says that it can be used and its for Nextion why then can put the link or something about the configuration using the Nextion Screen.. it is just my opinion, i like Nextion, Expanion Board, itead.. 

Vectorspace started this thread, thus Vectorspace put this title.  Vectorspace did include an HMI design which would include many hints to its use.  Itead also did make a YouTube video showing it in use ... I'll find the link.  -- YouTube Video.   You have also located the Nextion Instruction Set.  I will reiterate that a button is not configured, it is hardwired via a trace on the PCB.  There is nothing on this expansion board that isn't hardwired.

Therefore look to the silk that shows the button Esc is IO0, Enter IO1, Right is IO2, Down IO3, Up is IO4, Left is IO5, Led is IO6, And the Beep (Buzzer) is IO7.  Connect the Flex Cable between the board and the Nextion Display.  The Nextion Instruction Set and (see examples in the HMI) use the command cfgpio.

Actually Vectorspace gave plenty of info on how to use.

I like the Nextion and Itead too.  Personally, a board with buttons .. for me is unexciting, and this was well below Itead's previous product level and capabilities.  I am glad this board has to be connected and wasn't hardwired.  I am glad I have a choice to use Nextion IO for something else and I do not have to connect this to my Nextion.  I would rather use the Nextion IO lines to receive an image from an OV7670 cam, or extend communications to a PSF-A85 wifi. 

Since the Nextion is capable of 100's of virtual buttons, why would you put physical buttons less than 6 inches from the display and not merely program them into an HMI design.  A one tone buzzer is annoying at the pitch it sounds off at (see video or connect this board), and that leaves an LED, which my MCU has one already.  My question wouldn't be How to Use .. it would be Why Use At All.  My opinion.

Can I connect light sensor (optoresistor or optotransitor) into gpio ?

in general, you can connect all you like ... the remaining question is, if it may work as expected ... :-)

GPIO's are digital, not analogue ...

so, as long as your sensor delivers a digital signal ... on/off 0/1 ... it will work

Ofcourse ... thankx

what will work is e.g.

    - PIR IR sensors
    - buttons
    - all sensors with included Smith-Trigger
    - all analogue sensors with external Smith-Trigger
    - HAL sensors
    - REED
    - ...


Thankx alot

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