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Teensy 3.5 and Nextion7" examples do not seem to work ?

As it says I have a teensy 3.5 and I am trying the nextion examples like SLIDER ans several others , the 50 ( numbers ) do not change like the sketch says they should , I have verified that I have serial on serial3 for Teensy ( for an arduino it is serial2 ) I have some programs that I get serial monitoring so I know I have the right serial port. 

Are there any examples and or sketches for Teensy ?? 




Haven't forgotten about you.


  The base Iteadlib Arduino Nextion Library is written for AVR

   - UNO and Mega2560 supported.


   A library could be written for the Cortex M4

   Teensy 3.5 (Cortex M4) differs slightly from STM32F4

     - even though both ARM Mandated cores

       peripherals are under Manufacturer's control.


  Mostly programming Language and compiler tools

  will determine the examples

So a library would have to be written for the Teensy 3.5 etc. is this in the works or planned to be release at all ? 

Short answer is no, or most likely not by Itead.


Text based commands of Nextion are sent via serial

 - this forms the Nextion Instruction Set.


MCU side is user side, and this becomes not so clear.

over 10000 MCU types can be supported

  all that have TTL Serial or can bit bang two digital pins

Digikey lists almost 65900+ in microcontrollers alone

https://www.digikey.com/products/en/integrated-circuits-ics/embedded-microcontrollers/685

This doesn't include FPGAs, etc, etc.


Then you have the 130+ programming languages

  Pascal (my fav), C, C++, Python, Basic, Java ...

Then you have subsets and flavours within languages

   such as Arduno C++, javascript ...


Most important is the compiler and tool-chains to use for a given language

Within Pascal Delphi, Kylix, FreePascal, ... all have their own differences

mikroPascal for ARM differs again in which parts of programming language implemented

and even implementations for "the same functions" differs in requirements for calling conventions.


Libraries are sets of functional programming code

   Itead's Iteadlib focuses heavily on Touch Return Data 0x65

   and then there is code from a project misused as a "library"

  - some attempt software serial

  - some focus on built in Hardware uart modules

  - some become more complete (requiring more flash/sram_

  - some too skinny to really be considered a library

  - most coders consider theirs a library

    and perhaps as reusable code .. maybe so.


So Itead has provided IteadLib in

   - the Arduino Nextion Library and

   - the Segnix compatible library


But to even consider for all combinations of MCU/Language/Compiler

   is beyond human capability.


PIC, STM32, AVR, ESP-8266, TI, etc 

    write what is needed for their HMI design


Arduino being more "open source" gets shared more

Commercial implementations, less so

  companies  usually prefer to retain their IP and don't openly share.


Development typically means it can be done

  ultimately, someone must also pay for the development

Ok thanks for the info , back to using a Mega with the screen , we are sending numbers from the Nextion to the Mega to store in EEprom , the buttons are slow , like really slow to reply this is why I was looking into the Teensy to speed things up. Any tips/tricks to speed up this type of setup ? I can provide code if needed. 

the Arduino Mega is based on an Atmega m2560 Risc core MCU, executing instructions in a single clock cycle ...


By default, the Arduino Mega is clocked with 16 MHZ, means 16MIPS, 16 Million Instructions per second will be executed ...


If something such trivial as slow button query happens, the issue is for 100% sure not your hardware. With 16MIPS, your MCU is 99% of its power on time sleeping, snore and waiting for you ...


The reason for such slow button query is morelike a question of your running software ... and a wrong or awkwarded implemented algorithm is still awkward, independent on which final platform you will run it ... a Teensy won't help for such ...


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I have not used a Teensy but I don't believe there is an issue using that with the display.


I have used an STM32L4 chip with Arduino code with no issues running at 80 mhz.


Here is an example sketch: https://github.com/iseries1/GPSDisplay


Mike



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Thanks guys we are looking into it now , My guys says this happens , Im not a programmer so I am not sure what this means 



"from the looks of it nextion doesn't seems to have blocking call backs"

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